Hebrew Leap Year

#1
The code below includes a function to calculate if a Hebrew Year is a Hebrew Leap Year.

Code:
@setlocal
@echo off
function IsLeapYear=`%@eval[((%1 * 7 + 1) mod 19) < 7]`
::
:: Yom Rishon, Adar 21, 5770 is Sunday, March 7, 2010
::   After sunset, it will be Yom Sheni, Adar 22, 5770
::
do i=5770 to 5779
  if %@IsLeapYear[%i] eq 1 echo %i is a Hebrew Leap Year
enddo
unfunction IsLeapYear
endlocal
Joe