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A212557 Primes p such that (p, p-9) is an irregular pair. 1
67, 877 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No further terms found up to 163577833 in extended tables (see Buhler link). - Michel Marcus, Apr 17 2014

LINKS

Table of n, a(n) for n=1..2.

Joe Buhler and David Harvey, Irregular primes to 163 million, 2009.

W. Johnson, Irregular primes and Cyclotomic Invariants, Math. Comp., 1975, Vol. 29, No. 129, pp. 113-120.

PROG

(PARI) is(n)=lift(Mod(numerator(bernfrac(n-9)), n)==0)

forprime(p=8, , if(is(p), print1(p, ", "))) \\ Felix Fröhlich, Jan 19 2015

CROSSREFS

Special instances of A000928. Variant of A088164 (for the terms of A088164, (p, p-3) is an irregular pair).

Sequence in context: A106106 A093942 A166802 * A254640 A093267 A032651

Adjacent sequences:  A212554 A212555 A212556 * A212558 A212559 A212560

KEYWORD

nonn,hard,bref,more

AUTHOR

Felix Fröhlich, May 21 2012

STATUS

approved

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Last modified December 4 21:56 EST 2016. Contains 278755 sequences.