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Primes p such that (p, p-9) is an irregular pair.
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%I #35 Jan 23 2015 02:47:11

%S 67,877

%N Primes p such that (p, p-9) is an irregular pair.

%C No further terms found up to 163577833 in extended tables (see Buhler link). - _Michel Marcus_, Apr 17 2014

%H Joe Buhler and David Harvey, <a href="http://web.maths.unsw.edu.au/~davidharvey/papers/irregular/">Irregular primes to 163 million</a>, 2009.

%H W. Johnson, <a href="http://dx.doi.org/10.1090/S0025-5718-1975-0376606-9">Irregular primes and Cyclotomic Invariants</a>, Math. Comp., 1975, Vol. 29, No. 129, pp. 113-120.

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

%o forprime(p=8, , if(is(p), print1(p, ", "))) \\ _Felix Fröhlich_, Jan 19 2015

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

%K nonn,hard,bref,more

%O 1,1

%A _Felix Fröhlich_, May 21 2012