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A131261 a(0)=3; for n>0, a(n) = smallest odd prime not occurring earlier in the sequence such that a(n-1)+a(n) is a multiple of n. 2
3, 5, 7, 11, 13, 17, 19, 23, 41, 31, 29, 37, 47, 83, 43, 107, 53, 151, 101, 89, 71, 97, 79, 59, 61, 139, 173, 313, 163, 127, 113, 73, 311, 283, 193, 157, 131, 239, 103, 443, 197, 541, 257, 431, 229, 401, 887, 241, 191, 397, 353, 463, 109, 421, 227, 433, 631, 167 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Is this sequence infinite and, if so, is it a permutation of the odd primes?

An analog of A134204, but using only the odd primes.

LINKS

Olivier GĂ©rard, Table of n, a(n) for n = 0..1000

MATHEMATICA

a = {3}; For[n = 1, n < 60, n++, i = 2; While[Length[Intersection[{Prime[i]}, a]] == 1 || Not[Mod[a[[ -1 ]] + Prime[i], n] == 0], i++ ]; AppendTo[a, Prime[i]]]; a (* Stefan Steinerberger, Oct 30 2007 *)

CROSSREFS

Cf. A134204.

Sequence in context: A000978 A128925 A204142 * A100276 A225669 A065389

Adjacent sequences:  A131258 A131259 A131260 * A131262 A131263 A131264

KEYWORD

nonn

AUTHOR

David Applegate, Oct 26 2007

STATUS

approved

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Last modified December 5 07:41 EST 2016. Contains 278761 sequences.