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.

A202371 Number of (n+2)X3 binary arrays avoiding patterns 001 and 111 in rows and columns.

Original entry on oeis.org

98, 257, 611, 1326, 2815, 5718, 11362, 22164, 42507, 80633, 151352, 281811, 521224, 958418, 1754004, 3196693, 5805401, 10510754, 18978585, 34187852, 61457038, 110271668, 197530737, 353309613, 631087988, 1125880395, 2006365746
Offset: 1

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Author

R. H. Hardin Dec 18 2011

Keywords

Comments

Column 1 of A202378

Examples

			Some solutions for n=10
..1..1..0....1..0..0....1..0..0....0..1..1....1..1..0....0..1..1....1..0..1
..1..0..1....1..1..0....0..1..1....1..1..0....1..0..1....1..0..0....0..1..1
..0..1..0....0..0..0....1..1..0....1..0..1....0..1..0....0..1..1....1..0..0
..1..1..0....1..1..0....1..0..1....0..1..1....1..0..1....1..0..0....0..1..0
..0..0..0....1..1..0....0..1..0....1..0..0....0..1..0....0..1..1....1..1..0
..1..1..0....0..0..0....1..0..1....1..1..0....1..1..0....1..0..1....1..0..0
..0..0..0....1..1..0....0..1..1....0..0..0....1..0..0....0..0..0....0..1..0
..1..1..0....1..0..0....1..1..0....1..0..0....0..0..0....1..0..1....1..1..0
..1..0..0....0..1..0....1..0..1....1..0..0....1..0..0....1..0..1....1..0..0
..0..1..0....1..1..0....0..1..0....0..0..0....0..0..0....0..0..0....0..0..0
..0..0..0....0..0..0....1..0..1....1..0..0....1..0..0....1..0..1....0..0..0
..0..0..0....1..0..0....1..0..1....0..0..0....1..0..0....1..0..0....0..0..0
		

Formula

Empirical: a(n) = 2*a(n-1) +3*a(n-2) -2*a(n-3) -12*a(n-4) -a(n-5) +12*a(n-6) +15*a(n-7) -2*a(n-8) -8*a(n-9) -13*a(n-10) -5*a(n-11) +a(n-12) +8*a(n-13) +4*a(n-14) +2*a(n-15) -a(n-16) -a(n-17) -a(n-18)