login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A155894
Least positive integer such that a(n)! starts with n, both written in base 16.
3
1, 2, 10, 36, 9, 3, 5, 24, 8, 43, 82, 25, 30, 46, 64, 62, 60, 68, 7, 14, 70, 18, 13, 4, 31, 272, 19, 12, 97, 35, 161, 140, 20, 86, 27, 74, 131, 11, 502, 234, 47, 181, 386, 21, 6, 996, 52, 232, 144, 32, 393, 189, 199, 281, 10, 490, 39, 154, 83, 22, 28, 577, 63, 65, 88, 61, 115
OFFSET
1,2
LINKS
Nick Hobson, C program.
PROG
(PARI) A155894(n)={ local( F=1, k=1 ); while( F\1!=n, F*=k++; while( F>=n+1, F/=16 )); k}
(C) See Links section.
CROSSREFS
KEYWORD
base,nonn
AUTHOR
M. F. Hasler, Feb 01 2009
STATUS
approved