OFFSET
1,1
COMMENTS
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..10000
EXAMPLE
a(1) = 6 + 4 = 10;
a(2) = 11 + 8 = 19;
a(3) = 13 + 9 = 22.
MAPLE
A046953 := proc(n) if n = 1 then 6 ; else for a from procname(n-1)+1 do if not isprime(6*a-1) then return a; end if; end do: end if; end proc:
A046954 := proc(n) if n = 1 then 0 ; else for a from procname(n-1)+1 do if not isprime(6*a+1) then return a; end if; end do: end if; end proc:
seq(A173231(n), n=1..120) ; # R. J. Mathar, May 02 2010
MATHEMATICA
PROG
(Magma)
A046953:=[n: n in [1..250] | not IsPrime(6*n-1)];
A046954:=[n: n in [0..250] | not IsPrime(6*n+1)];
(Sage)
A046953=[n for n in (1..250) if not is_prime(6*n-1)];
A046954=[n for n in (0..250) if not is_prime(6*n+1)];
(GAP)
A046953:=Filtered([1..250], k-> not IsPrime(6*k-1));;
A046954:=Filtered([0..250], n-> not IsPrime(6*n+1));;
CROSSREFS
KEYWORD
nonn
AUTHOR
Juri-Stepan Gerasimov, Feb 13 2010, Feb 15 2010
EXTENSIONS
Entries checked by R. J. Mathar, May 02 2010
STATUS
approved