OFFSET
1,4
EXAMPLE
a(1) = abs(6*1 + 1 - (6*1 - 1))/2 = 1;
a(2) = abs(6*2 + 1 - (6*2 - 1))/2 = 1.
MAPLE
A002476 := proc(n) if n = 1 then 7; else for a from procname(n-1)+6 by 6 do if isprime(a) then return a; end if; end do: end if; end proc:
A007528 := proc(n) if n = 1 then 5; else for a from procname(n-1)+6 by 6 do if isprime(a) then return a; end if; end do: end if; end proc:
A171716 := proc(n) A002476(n)-A007528(n) ; abs(%)/2 ; end proc: seq(A171716(n), n=1..120) ; # R. J. Mathar, May 22 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Dec 17 2009
EXTENSIONS
a(26) corrected by R. J. Mathar, May 22 2010
STATUS
approved