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A223881 Denominators in the expression m!/(prime(m-1)+1) for m > 1 such that this expression is not an integer. 2
3, 2, 19, 31, 37, 79, 41, 97, 53, 139, 71, 157, 83, 199, 211, 229, 131, 271, 137, 307, 331, 337, 173, 367, 379, 197, 439, 227, 499, 263, 547, 281, 577, 293, 197, 199, 601, 607, 619, 661, 227, 229, 691, 239, 727, 383, 269, 811, 829, 283, 431, 877, 467, 937, 313 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It appears that all terms are primes.

LINKS

Paolo P. Lava, Table of n, a(n) for n = 1..1000

MAPLE

with(numtheory); A223881:=proc(q) local a, k, m;

for m from 2 to q do a:=m!/(ithprime(m-1)+1);

if not type(a, integer) then print(denom(a)); fi;

od; end: A223881(10^6); # Paolo P. Lava, May 07 2013

MATHEMATICA

Denominator[Select[Table[m!/(Prime[m - 1] + 1), {m, 2, 300}], ! IntegerQ[#] &]] (* T. D. Noe, May 03 2013 *)

PROG

(PARI) m=M=1; forprime(p=2, 1e5, M*=m++; t=denominator(M/(p+1)); if(t>1, print1(t", "))) \\ Charles R Greathouse IV, May 08 2013

CROSSREFS

Cf. A007528, A024898, A002476, A091178.

Sequence in context: A066195 A090587 A094554 * A206582 A154262 A154261

Adjacent sequences:  A223878 A223879 A223880 * A223882 A223883 A223884

KEYWORD

nonn

AUTHOR

Alexander R. Povolotsky, May 01 2013

STATUS

approved

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Last modified August 2 09:22 EDT 2021. Contains 346422 sequences. (Running on oeis4.)