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A092217 Primes that do not divide any Euler number. 5
2, 3, 7, 11, 23, 59, 83, 103, 107, 127, 131, 151, 163, 167, 179, 191, 199, 211, 227, 239, 271, 283, 331, 347, 367, 383, 431, 439, 443, 467, 479, 487, 499, 503, 523, 547, 599, 607, 631, 643, 647, 659, 683, 719, 727, 743, 787, 823, 827, 839, 859, 863, 883, 911 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

After computing the Euler numbers, finding the non-divisors is simple because the Euler numbers satisfy a Kummer congruence. See Wagstaff for details. The density of these primes is approximately 0.33.

LINKS

T. D. Noe, Table of n, a(n) for n = 1..264

S. S. Wagstaff, Jr., Prime divisors of the Bernoulli and Euler numbers

Eric Weisstein's World of Mathematics, Euler Number

MATHEMATICA

ee=Table[Abs[EulerE[2i]], {i, 1000}]; t=Table[p=Prime[n]; cnt=0; Do[If[Mod[ee[[i]], p]==0, cnt++ ], {i, p}]; cnt, {n, PrimePi[1000]}]; Prime[Flatten[Position[t, 0]]]

CROSSREFS

Cf. A000364 (Euler numbers), A092218 (primes that divide some Euler number), A092219.

Sequence in context: A227199 A129940 A128631 * A191659 A007481 A238312

Adjacent sequences:  A092214 A092215 A092216 * A092218 A092219 A092220

KEYWORD

nonn

AUTHOR

T. D. Noe, Feb 25 2004

STATUS

approved

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Last modified February 21 06:25 EST 2018. Contains 299390 sequences. (Running on oeis4.)