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

%I

%S 2,3,13,19,22,38,39,45,48,60,62,66,68,79,83,89,100,101,102,113,122,

%T 123,126,131,135,139,152,156,169,178,184,189,192,194,195,197,198,199,

%U 204,217,219,221,222,228,232,243,256,258,261,266,270,274,286,288,289,292

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

%H G. C. Greubel, <a href="/A225517/b225517.txt">Table of n, a(n) for n = 1..1100</a>

%t Select[Range[2, 522], ! IntegerQ[#!/(Prime[# - 1] + 1)] &] (* _T. D. Noe_, May 10 2013 *)

%o (PARI) m=M=1; forprime(p=2, 1e5, M*=m++; t=denominator(M/(p+1)); if(t>1, print1(m", ")))

%Y Cf. A223881.

%K nonn

%O 1,1

%A _Alexander R. Povolotsky_, May 09 2013

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Last modified August 4 09:55 EDT 2021. Contains 346446 sequences. (Running on oeis4.)