A018790 Number of subsets of { 1, ..., n } containing an A.P. of length 5.

0, 0, 0, 0, 0, 1, 3, 8, 20, 56, 144, 332, 751, 1803, 4163, 9401, 20404, 45169, 98753, 213575, 457945, 990624, 2119184, 4493766, 9460916, 19947914, 41567180, 86219409, 178237782, 369985101, 765030649, 1572706886, 3224800994, 6617409989

Offset

0,7

Links

Table of n, a(n) for n=0..33.

Crossrefs

Sequence in context: A018035 A271843 A122228 * A268042 A009436 A354519

Adjacent sequences: A018787 A018788 A018789 * A018791 A018792 A018793

Keyword

nonn

Author

David W. Wilson

Status

approved