cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A225517 Integers n > 1 such that expression n!/(prime(n-1)+1) is not an integer.

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%I A225517 #12 Feb 27 2017 02:56:49
%S A225517 2,3,13,19,22,38,39,45,48,60,62,66,68,79,83,89,100,101,102,113,122,
%T A225517 123,126,131,135,139,152,156,169,178,184,189,192,194,195,197,198,199,
%U A225517 204,217,219,221,222,228,232,243,256,258,261,266,270,274,286,288,289,292
%N A225517 Integers n > 1 such that expression n!/(prime(n-1)+1) is not an integer.
%H A225517 G. C. Greubel, <a href="/A225517/b225517.txt">Table of n, a(n) for n = 1..1100</a>
%t A225517 Select[Range[2, 522], ! IntegerQ[#!/(Prime[# - 1] + 1)] &] (* _T. D. Noe_, May 10 2013 *)
%o A225517 (PARI) m=M=1; forprime(p=2, 1e5, M*=m++; t=denominator(M/(p+1)); if(t>1, print1(m", ")))
%Y A225517 Cf. A223881.
%K A225517 nonn
%O A225517 1,1
%A A225517 _Alexander R. Povolotsky_, May 09 2013