A004787 Numbers k such that 7!*(2k-8)!/(k!*(k-1)!) is an integer.

4, 7, 8, 991, 2481, 3479, 5645, 6163, 6581, 8178, 8179, 8242, 9272, 10288, 12195, 13067, 13976, 15199, 15813, 16172, 18329, 18371, 18686, 18723, 18747, 19294, 19438, 22198, 23531, 23717, 26198, 26315, 26678, 27877, 28429, 30553, 30593, 30689, 31327

Offset

1,1

Links

Table of n, a(n) for n=1..39.

Mathematica

Select[Range[10^4], IntegerQ[7! (2 # - 8)!/(#! (# - 1)!)] &] (* Arkadiusz Wesolowski, Sep 06 2011 *)

Crossrefs

Sequence in context: A093105 A141669 A190967 * A210617 A191762 A107905

Adjacent sequences: A004784 A004785 A004786 * A004788 A004789 A004790

Keyword

nonn

Author

R. K. Guy

Extensions

More terms from David W. Wilson, Dec 11 1999

Offset corrected and 2 initial terms added by Arkadiusz Wesolowski, Sep 06 2011

Status

approved