The following code is the adaptation of the Python code found here. The code below has limited the loop so that the weekends generated are only within the year of interest. After having completed the period of interest, it just flashes the LED using the Blink sketch. An earlier version did not have this limitation and rushed off to find all of the weekends (successfully) out to the limits of what the unsigned long variables could hold.

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The sketch below can be downloaded from here: LogicTester.ino

/*
The following is a program to develop the logic for setting and triggering the alarms
in the Arduino Timer Project
The array used is the same array as the Arduino gets from the SD Card.
*/
unsigned long times[] = {1386347400,1386563400,1387548000,1389155400,1389967200,1390278600,1397743200,1398141000,1398348000,1398659400,1401458400,1401769800,1414159200,1414470600};
int NoF = 14;  // This is the number ofcomponents in the array. This figure is generated in the
               // array loading section of the project.
unsigned long NowTime=1386347000;    // This is the current time in Unix Time format. This will come from the RTC
boolean StatusFlag = false;  // Is the HWC enabled or not?
boolean RedLED = false; //LED pin control.This will be used to indicate the Red LED state for available times exceeded. Basically if this goes off you will need to put more dates in the SD Card
boolean YellowLED=false; //Yellow LED indicator to show that the HWC element is enabled.
boolean GreenLED=false;  //Green LED indicater to show that the system is working.
int InDexer = 2;	//InDexer is the array pointer that indicates which is the next holiday period to be used.
unsigned long AlarmDateOn=0;	//This is justa holder to help with debugging - real alarms will be used instead when coded for real
unsigned long AlarmDateOff=0;	//This is another holder to help with debugging - real alarms will be used instead when coded for real
boolean Completed = false;    //This just signals completion of the loop.
int ledPin = 13;	// LED connected to digital pin 13

void setup()
{
  pinMode(ledPin, OUTPUT);
  //Open Serial Communications and wait for the port to open:
  Serial.begin(9600);
  // Make all weekend alarm dates and holiday period pointers current.
  Serial.println(NowTime);
  Serial.print(times[0]),Serial.print(","),Serial.println(times[1]);
  if (times[0]< NowTime)	// The following updates the weekend dates to be in the future.
  {
    while (times[0]<NowTime)
    {
      times[0]=times[0]+604800;    // Add a week's worth of seconds
      times[1]=times[1]+604800;
    }
  }
	
  // Step through the times[] array components to find the next START of the holiday period.
  while (times[InDexer]<NowTime)	// Check to see if the date is in the future.
  {
    InDexer = InDexer + 2;       // Adding two means we look ONLY at the start dates.
    if (InDexer >= NoF-1)	//  Have we exceeded the list?  If so enable the error light
    {
      RedLED = true;
      break;
    }
  }
  // Report the next weekend and whether the list of special breaks has been exceeded.
  Serial.print(times[0]);Serial.print(",");Serial.println(times[1]);
  Serial.print(RedLED);
  Serial.print(InDexer);	//This indicates where in the list of holiday breaks we are looking and the next holidays.
  Serial.print("Holiday Alarm");Serial.print(times[InDexer]);Serial.println(times[InDexer+1]);
}


void loop()
{
	// The following section will loop the NowTime to simulate the info from the RTC.
	// To carry over into this new section the up-to-date InDexer will be used to work out
	// Which Holiday periods are coming up and which alarm goes next. InDexer is a Global Variable.
	// The Weekends will be set to skip forward if it turns out that a holiday period is
	// coming up next.
        // Although the loop allows us to repeatedly loop through the process
        // and does give the right dates for weekends many years in the future
        // we will limit the loop to being just a first year so that we can examine the
        // holiday dates. Once it is done we will set the LED to flash so that the
        // loop is kept occupied.
  while(Completed == false)      //This limits the looping. 
    {
    unsigned long dd = AlarmDateOn;    //This is justa holder to help with debugging - these carry the old values of the alarms
    unsigned long ee = AlarmDateOff;    //This is another holder to help with debugging -  these carry the old values of the alarms
    if (times[0]> times[InDexer] && RedLED == true) // It would be a holiday but the list has been exceeded
	{
		AlarmDateOn = times[0];    // In the Arduino this will load the date into the Alarm function
		AlarmDateOff = times[1];
	}
    else if (times[0]>times[InDexer] && RedLED == false) // The next item is a holiday and the list is OK.
	{
        AlarmDateOn = times[InDexer];
        AlarmDateOff = times[InDexer+1];  // Loads the Holiday times into the Alarm function
        while (times[0]< times[InDexer+1])
		{
            times[0]=times[0]+604800;    //Advance the weekend dates to be clear of the holiday
            times[1]=times[1]+604800;
		}
    }
	else								//Normal Weekend
	{
        AlarmDateOn = times[0];			//In the Arduino this will load the date into the Alarm function
        AlarmDateOff = times[1];
	}
	
    if (NowTime > times[1])	// When a weekend start has passed jump forward to the next one.  We shall have to check that the logic
							// does not cause the weekend close off alarm to be overwritten.
	{
        times[0]=times[0]+604800;    // Advance the weekend dates to the next one once the
        times[1]=times[1]+604800;    // current weekend is finished
	}
    if (NowTime > times[InDexer+1])	//When a holiday is in progress the pointer needs to be advanced.
	{
        InDexer = InDexer+2;	//Advance the pointer the the next holiday once current one
								//finished.
        if (InDexer >= NoF-1)	//Have we exceeded the list?  If so enable the error light
		{
            RedLED = true;			//But carry on by setting InDexer to last good figure
            InDexer = InDexer - 2;
		}
    }
	// The following is to simulate the operation of the alarms.  If needed we can print the Status flags to the serial port.
	// We will need to look at the looptime step size if we do implement this as it is likely to miss the reporting times.
	if (NowTime == AlarmDateOn)
	{
          StatusFlag = true;
          YellowLED = true;
	}
        if (NowTime == AlarmDateOff)
	{
          StatusFlag = false;
          YellowLED = false;
	}
        if (dd != AlarmDateOn)   //The following lines are to produce a new dump of the alarms
	{
	  Serial.println(AlarmDateOn); // Whenever a date change is triggered - print the new alarm settings.
        }
        if (ee != AlarmDateOff)
	{
	  Serial.println(AlarmDateOff);
	}
    NowTime = NowTime + 500;
    if(NowTime >= 1419309000)
    {
      Completed = true;
    }
  }
  digitalWrite(ledPin, HIGH);	// set the LED on
  delay(1000);			// wait for a second
  digitalWrite(ledPin, LOW);	// set the LED off
  delay(1000);			// wait for a second
}

This is a subset of the output sent to the Serial Monitor.

1386347400	Friday, 6 December 2013 16:30
1386563400	Monday, 9 December 2013 04:30
1386952200	Friday, 13 December 2013 16:30
1387168200	Monday, 16 December 2013 04:30
1387548000	Friday, 20 December 2013 14:00
1389155400	Wednesday, 8 January 2014 04:30
1389371400	Friday, 10 January 2014 16:30
1389587400	Monday, 13 January 2014 04:30
1389967200	Friday, 17 January 2014 14:00
1390278600	Tuesday, 21 January 2014 04:30
1390581000	Friday, 24 January 2014 16:30
1390797000	Monday, 27 January 2014 04:30
1391185800	Friday, 31 January 2014 16:30
1391401800	Monday, 3 February 2014 04:30
1391790600	Friday, 7 February 2014 16:30
1392006600	Monday, 10 February 2014 04:30
1392395400	Friday, 14 February 2014 16:30
1392611400	Monday, 17 February 2014 04:30
1393000200	Friday, 21 February 2014 16:30
1393216200	Monday, 24 February 2014 04:30
1393605000	Friday, 28 February 2014 16:30
1393821000	Monday, 3 March 2014 04:30
1394209800	Friday, 7 March 2014 16:30
1394425800	Monday, 10 March 2014 04:30
1394814600	Friday, 14 March 2014 16:30
1395030600	Monday, 17 March 2014 04:30
1395419400	Friday, 21 March 2014 16:30
1395635400	Monday, 24 March 2014 04:30
1396024200	Friday, 28 March 2014 16:30
1396240200	Monday, 31 March 2014 04:30
1396629000	Friday, 4 April 2014 16:30
1396845000	Monday, 7 April 2014 04:30
1397233800	Friday, 11 April 2014 16:30
1397449800	Monday, 14 April 2014 04:30
1397743200	Thursday, 17 April 2014 14:00
1398141000	Tuesday, 22 April 2014 04:30
1398348000	Thursday, 24 April 2014 14:00
1398659400	Monday, 28 April 2014 04:30
1399048200	Friday, 2 May 2014 16:30
1399264200	Monday, 5 May 2014 04:30
1399653000	Friday, 9 May 2014 16:30
1399869000	Monday, 12 May 2014 04:30
1400257800	Friday, 16 May 2014 16:30
1400473800	Monday, 19 May 2014 04:30
1400862600	Friday, 23 May 2014 16:30
1401078600	Monday, 26 May 2014 04:30
1401458400	Friday, 30 May 2014 14:00
1401769800	Tuesday, 3 June 2014 04:30
1402072200	Friday, 6 June 2014 16:30
1402288200	Monday, 9 June 2014 04:30
1402677000	Friday, 13 June 2014 16:30
1402893000	Monday, 16 June 2014 04:30
1403281800	Friday, 20 June 2014 16:30
1403497800	Monday, 23 June 2014 04:30
1403886600	Friday, 27 June 2014 16:30
1404102600	Monday, 30 June 2014 04:30
1404491400	Friday, 4 July 2014 16:30
1404707400	Monday, 7 July 2014 04:30
1405096200	Friday, 11 July 2014 16:30
1405312200	Monday, 14 July 2014 04:30
1405701000	Friday, 18 July 2014 16:30
1405917000	Monday, 21 July 2014 04:30
1406305800	Friday, 25 July 2014 16:30
1406521800	Monday, 28 July 2014 04:30
1406910600	Friday, 1 August 2014 16:30
1407126600	Monday, 4 August 2014 04:30
1407515400	Friday, 8 August 2014 16:30
1407731400	Monday, 11 August 2014 04:30
1408120200	Friday, 15 August 2014 16:30
1408336200	Monday, 18 August 2014 04:30
1408725000	Friday, 22 August 2014 16:30
1408941000	Monday, 25 August 2014 04:30
1409329800	Friday, 29 August 2014 16:30
1409545800	Monday, 1 September 2014 04:30
1409934600	Friday, 5 September 2014 16:30
1410150600	Monday, 8 September 2014 04:30
1410539400	Friday, 12 September 2014 16:30
1410755400	Monday, 15 September 2014 04:30
1411144200	Friday, 19 September 2014 16:30
1411360200	Monday, 22 September 2014 04:30
1411749000	Friday, 26 September 2014 16:30
1411965000	Monday, 29 September 2014 04:30
1412353800	Friday, 3 October 2014 16:30
1412569800	Monday, 6 October 2014 04:30
1412958600	Friday, 10 October 2014 16:30
1413174600	Monday, 13 October 2014 04:30
1413563400	Friday, 17 October 2014 16:30
1413779400	Monday, 20 October 2014 04:30
1414159200	Friday, 24 October 2014 14:00
1414470600	Tuesday, 28 October 2014 04:30
1414773000	Friday, 31 October 2014 16:30
1414989000	Monday, 3 November 2014 04:30
1415377800	Friday, 7 November 2014 16:30
1415593800	Monday, 10 November 2014 04:30
1415982600	Friday, 14 November 2014 16:30
1416198600	Monday, 17 November 2014 04:30
1416587400	Friday, 21 November 2014 16:30
1416803400	Monday, 24 November 2014 04:30
1417192200	Friday, 28 November 2014 16:30
1417408200	Monday, 1 December 2014 04:30
1417797000	Friday, 5 December 2014 16:30
1418013000	Monday, 8 December 2014 04:30
1418401800	Friday, 12 December 2014 16:30
1418617800	Monday, 15 December 2014 04:30
1419006600	Friday, 19 December 2014 16:30
1419222600	Monday, 22 December 2014 04:30
1419611400	Friday, 26 December 2014 16:30
1419827400	Monday, 29 December 2014 04:30