A155896 Least positive integer such that a(n)! starts with n, both written in base 6.

1, 2, 5, 4, 8, 3, 9, 26, 52, 18, 25, 10, 33, 53, 32, 15, 13, 20, 30, 5, 17, 42, 7, 4, 23, 43, 78, 50, 28, 113, 8, 44, 19, 334, 59, 100, 195, 27, 22, 14, 91, 172, 371, 16, 93, 9, 12, 102, 66, 26, 46, 95, 279, 303, 69, 331, 272, 52, 286, 79, 264, 298, 18, 21, 190, 104, 47, 138, 255

Offset

1,2

Links

Table of n, a(n) for n=1..69.

Example

a(3) = 5 since 5!=120 is the least factorial to start with digit "3" when written in base 6. a(8) = 26 since 8 = 12[6] (i.e. written in base 6) and 26! is the smallest factorial to start with digits "12" when written in base 6.

Prog

(PARI) A155896(n)={ local( F=1, k=1 ); while( F\1!=n, F*=k++; while( F>=n+1, F/=6)); k}

Crossrefs

Cf. A155891--A155894, A018799, A076219.

Sequence in context: A140869 A111570 A057954 * A060710 A271853 A146101

Adjacent sequences: A155893 A155894 A155895 * A155897 A155898 A155899

Keyword

base,nonn

Author

M. F. Hasler, Feb 01 2009

Status

approved