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A328703 Numbers k dividing nonzero terms in A002065. 2
1, 3, 13, 39, 61, 151, 169, 183, 211, 223, 453, 507, 633, 669, 739, 793, 1009, 1531, 1963, 2197, 2217, 2379, 2743, 2899, 3027, 3721, 4363, 4513, 4593, 5503, 5889, 6277, 6397, 6591, 7753, 7873, 8229, 8697, 9211, 9463, 9607, 10309, 11163, 11353, 11587, 11677, 12007, 12241, 12871 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

k is a term if and only if A328702(k) = 0, in which case all the indices m such that k divides A002065(m) are m = t*A328701(k), t = 0, 1, 2, 3, ...

LINKS

Table of n, a(n) for n=1..49.

EXAMPLE

61 divides A002065(7) = 61, so 61 is in this sequence. In addition, 61 divides A002065(m) if and only if 4 divides m.

31 is not a term: {A002065(n) mod 31} = {0, 1, 3, 13, 28, 7, 26, 21, 29, 3, 13, 28, 7, 26, 21, 29, ...}, so 31 does not divides A002065(m) for any m > 0.

PROG

(PARI) v(n) = my(v=[0], k, flag=1); for(i=2, n+1, k=(v[#v]^2+v[#v]+1)%n; v=concat(v, k); for(j=1, i-1, if(v[j]==k, flag=0)); if(flag==0, break())); v

a(n) = !(v(n)[#v(n)])

CROSSREFS

Cf. A002065, A328701, A328702.

The primes in this sequence are given by A328704.

Sequence in context: A054975 A072790 A323009 * A166911 A103657 A320661

Adjacent sequences: A328700 A328701 A328702 * A328704 A328705 A328706

KEYWORD

nonn

AUTHOR

Jianing Song, Oct 26 2019

STATUS

approved

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Last modified January 29 00:02 EST 2023. Contains 359905 sequences. (Running on oeis4.)