cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A188841 Number of n X 7 binary arrays without the pattern 0 1 diagonally or vertically.

Original entry on oeis.org

128, 987, 3280, 7753, 15504, 28101, 47652, 76912, 119416, 179630, 263120, 376740, 528840, 729495, 990756, 1326924, 1754848, 2294248, 2968064, 3802832, 4829088, 6081801, 7600836, 9431448, 11624808, 14238562, 17337424, 20993804, 25288472
Offset: 1

Views

Author

R. H. Hardin, Apr 12 2011

Keywords

Comments

Column 7 of A188843.

Examples

			Some solutions for 3 X 7:
..1..1..0..0..1..1..1....1..1..1..1..1..1..1....1..0..0..1..1..0..0
..1..1..0..0..0..1..1....1..1..0..1..1..1..1....1..0..0..0..1..0..0
..1..1..0..0..0..0..0....0..0..0..0..0..0..0....1..0..0..0..0..0..0
		

Crossrefs

Cf. A188843.

Formula

Empirical: a(n) = (1/5040)*n^7 + (1/72)*n^6 + (143/360)*n^5 + (53/9)*n^4 + (33667/720)*n^3 + (12679/72)*n^2 + (9439/70)*n - 572 for n>4.
Empirical g.f.: x*(128 - 37*x - 1032*x^2 + 1981*x^3 - 992*x^4 - 605*x^5 + 700*x^6 - 58*x^7 - 96*x^8 + 3*x^9 + 8*x^10 + x^11) / (1 - x)^8. - Colin Barker, May 01 2018