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Indices n of odd numbers of the form 8*n+1 that are not primes.
1

%I #10 Aug 12 2015 21:19:47

%S 0,1,3,4,6,7,8,10,13,15,16,18,19,20,21,22,23,25,26,27,28,31,33,34,36,

%T 37,38,40,41,43,45,46,47,48,49,52,53,55,58,59,60,61,62,63,64,66,67,68,

%U 69,70,73,76,78,79,81,82,83,85,86,87,88,89,90,91,92,93,94,97,98,99,100,102

%N Indices n of odd numbers of the form 8*n+1 that are not primes.

%C Could be generated from A045751 by removing all odd terms there, then halving each remaining term. - _R. J. Mathar_, Jun 08 2007

%p isA127260 := proc(n) not isprime(8*n+1) ; end: for n from 0 to 200 do if isA127260(n) then printf("%d, ",n) ; fi ; od ; # _R. J. Mathar_, Jun 08 2007

%t a = Flatten[Table[If[PrimeQ[8*n + 1] == False, n, {}], {n, 0, 50}]]

%Y Cf. A045751.

%K nonn

%O 1,3

%A _Roger L. Bagula_, May 17 2007

%E More terms from _R. J. Mathar_, Jun 08 2007