This year it was on the news about 2012 having 3 Friday the thirteenths and the one in January to the one in April were 13 weeks apart. Here is the full story

2012 has January, April, and July, 3 Friday 13 
2112 has May with 1 Friday 13.
2212 has March with 1 Friday 13.
2312 has September with 1 Friday 13.
2412 has January, April, and July- 3 Friday 13. (Going to 400 more years later to...)
2812 has January, April, and July- 3 Friday 13. (Going to 400 more years later to....)
3212 has January, April, and July- 3 Friday 13.

2412 January, April and July- 3 Friday 13 
From January to April =91 days=13 weeks apart
So does any year that has 3 Friday 13. That year will have 91 days, which is 13 weeks that are from January 13 to April 13.

*NOTE* April 13 to July 13 starting with the 13 in April and counting to July 12 is 103 days. 1+0+3=4
*NOTE* 400 Years before 2012 was 1612. 1612 had the same months/3 Fridays which were January, April and July.
Same amount of days. 91 and 103.

Researched by
Bob Gray Smith
262791714928=58/13/4
7-13,14,15-2012
The Code
A=1; B=2;C=3;D=4;-M=13;-V=22/4;Z=26/8