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A095194
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Least number which yields a semiprime when appended to n!.
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1
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0, 1, 2, 7, 2, 1, 1, 1, 1, 1, 2, 1, 1, 7, 17, 1, 1, 1, 31, 13, 1, 59, 13, 7, 1, 61, 41, 37, 31, 1, 7, 7, 1, 2, 5, 61, 41, 7, 13, 37, 61, 43, 1, 1, 47, 67, 1, 3, 67, 61, 5, 19, 5, 11, 7, 13, 1, 3, 1, 71, 11, 1, 67, 109, 103, 43, 29
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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EXAMPLE
| Refers to the semiprimes 10, 21, 62, 247, 1202, 7201, 50401, 403201 etc..
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MAPLE
| A095194 := proc(n) local nf, i, ns ; nf := convert(n!, base, 10) ; for i from 1 do ns := [op(convert(i, base, 10)), op(nf)] ; add( op(j, ns)*10^(j-1), j=1..nops(ns)) ; if numtheory[bigomega](%) = 2 then return i ; end if; end do: end proc: # R. J. Mathar, Jun 17 2011
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PROG
| (PARI) a(n)=for(i=0, 1e9, bigomega(eval(Str(n!, i)))==2 & return(i)) \\ - M. F. Hasler, Jun 17 2011
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CROSSREFS
| Cf. A068845, A001358.
Sequence in context: A139339 A090986 A195726 * A095711 A102886 A204382
Adjacent sequences: A095191 A095192 A095193 * A095195 A095196 A095197
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KEYWORD
| base,nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Jun 21 2004
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EXTENSIONS
| Corrected and extended by Sean A. Irvine (sairvin(AT)xtra.co.nz), Jun 16 2011
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