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A213353 A subset of numbers n such that n^4 is a Sierpinski number. 4
44745755, 1812338107, 9266824499, 12308871853, 13657352875, 22767480811, 22930161667, 24068927659, 25549554505, 25770503549, 57939582163, 90219135299, 90329609821, 96949951147, 103126759951 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A sequence constructed from Izotov's trick.

If n belongs to this sequence and n does not end in 5, then n^4 has the covering set {3, 5, 17, 97, 241, 257, 673}.

LINKS

Table of n, a(n) for n=1..15.

Anatoly S. Izotov, A note on Sierpinski numbers

Wikipedia, Sierpinski number

MATHEMATICA

(* even if nn is increased, no additional terms are generated *) nn = 14; lst = {}; n = 44745755; p = 2^12; m = 3*(p^4 - 1)/(p - 1); Do[a = n + (-1)^c*m; n = a/GCD[a, p]; AppendTo[lst, Abs@n], {c, 0, nn}]; Union@lst

CROSSREFS

Subset of A233469. Cf. A076336.

Sequence in context: A270611 A049360 A130913 * A205263 A087534 A183747

Adjacent sequences:  A213350 A213351 A213352 * A213354 A213355 A213356

KEYWORD

nonn,easy,fini,full

AUTHOR

Arkadiusz Wesolowski, Jun 09 2012

STATUS

approved

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Last modified May 25 02:12 EDT 2022. Contains 354047 sequences. (Running on oeis4.)