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A095192 Smallest semiprime with same leading digits as n!. 0
10, 21, 62, 247, 1202, 7201, 50401, 403201, 3628801, 36288001, 399168002, 4790016001, 62270208001, 871782912007, 130767436800017, 209227898880001, 3556874280960001, 64023737057280001, 12164510040883200031 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..19.

MATHEMATICA

ssp[n_]:=Module[{f=n!, k=0}, While[PrimeOmega[10^Max[IntegerLength[k], 1] f+k]!=2, k++]; 10^Max[1, IntegerLength[k]] f+k]; Array[ssp, 20] (* Harvey P. Dale, May 05 2019 *)

CROSSREFS

Cf. A068844, A001358.

Sequence in context: A156592 A045973 A095679 * A096564 A041196 A082669

Adjacent sequences:  A095189 A095190 A095191 * A095193 A095194 A095195

KEYWORD

base,nonn

AUTHOR

Jason Earls, Jun 21 2004

STATUS

approved

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Last modified May 9 13:42 EDT 2021. Contains 343742 sequences. (Running on oeis4.)