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A127260 Indices n of odd numbers of the form 8*n+1 that are not primes. 1
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, 37, 38, 40, 41, 43, 45, 46, 47, 48, 49, 52, 53, 55, 58, 59, 60, 61, 62, 63, 64, 66, 67, 68, 69, 70, 73, 76, 78, 79, 81, 82, 83, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 97, 98, 99, 100, 102 (list; graph; refs; listen; history; internal format)
OFFSET

1,3

COMMENTS

Could be generated from A045751 by removing all odd terms there, then halving each remaining term. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 08 2007

MAPLE

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 (mathar(AT)strw.leidenuniv.nl), Jun 08 2007

MATHEMATICA

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

CROSSREFS

Cf. A045751.

Sequence in context: A007378 A087758 A105454 * A089530 A201820 A191775

Adjacent sequences:  A127257 A127258 A127259 * A127261 A127262 A127263

KEYWORD

nonn

AUTHOR

Roger L. Bagula (rlbagulatfttn(AT)yahoo.com), May 17 2007

EXTENSIONS

More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jun 08 2007

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Last modified February 14 11:36 EST 2012. Contains 205623 sequences.