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A048858 Number of prime factors of 1+(n!)^2 (with multiplicity). 0
1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 2, 1, 3, 2, 2, 2, 2, 2, 5, 3, 4, 3, 1, 3, 5, 7, 2, 2, 6, 4, 4, 5, 4, 3, 3, 3, 4, 4, 4, 2, 5, 5, 7, 2, 3, 8, 9, 3, 3, 4, 3, 2, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,7

LINKS

Table of n, a(n) for n=0..54.

H. Ibstedt, A Few Smarandache Integer Sequences, Smarandache Notions Journal, Vol. 8, No. 1-2-3, 1997, pp. 171-183.

MATHEMATICA

Table[Length[FactorInteger[1 + (n!)^2]], {n, 0, 20}] (* T. D. Noe, Oct 17 2011 *)

PROG

(PARI) a(n)=bigomega(n!^2+1) \\ Charles R Greathouse IV, Sep 20 2012

CROSSREFS

Sequence in context: A199840 A126067 A238408 * A246465 A172497 A211226

Adjacent sequences:  A048855 A048856 A048857 * A048859 A048860 A048861

KEYWORD

more,nonn

AUTHOR

Charles T. Le (charlestle(AT)yahoo.com)

EXTENSIONS

Corrected by Arkadiusz Wesolowski, Oct 17 2011

Corrected by Charles R Greathouse IV, Sep 20 2012

a(38)-a(54) from Giovanni Resta, Jun 26 2018

STATUS

approved

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Last modified April 22 10:36 EDT 2019. Contains 322330 sequences. (Running on oeis4.)