A262331 Number of (n+1)X(7+1) 0..1 arrays with each row and column divisible by 3, read as a binary number with top and left being the most significant bits.

86, 783, 65610, 2767631, 237172426, 16940254423, 1456404454010, 119519290640511, 10278397804194666, 873639089311509863, 75132812815390491610, 6442513290262072850191, 554056059394660086575306

Offset: 1

Author

R. H. Hardin, Sep 18 2015

Keywords

• nonn

Comments

Column 7 of A262332.

Examples

			Some solutions for n=3
..0..0..1..0..1..1..0..1....1..0..0..1..1..1..0..0....1..0..1..0..0..1..0..1
..0..0..1..0..1..1..0..1....0..1..0..1..1..1..0..1....1..0..1..0..0..1..0..1
..1..0..0..0..0..1..1..1....0..1..0..1..0..0..0..1....0..1..1..0..1..1..0..0
..1..0..0..0..0..1..1..1....1..0..0..1..0..0..0..0....0..1..1..0..1..1..0..0
		

Links

• R. H. Hardin, Table of n, a(n) for n = 1..210

Crossrefs

Cf. A262332.

Formula

Empirical: a(n) = 86*a(n-1) +3252*a(n-2) -279672*a(n-3) -3329646*a(n-4) [phone]*a(n-5) [phone]*a(n-6) -132834194760*a(n-7) -365579378025*a(n-8) [phone]*a(n-9) [phone]*a(n-10) -3985022198954544*a(n-11) -3102790005466128*a(n-12) +266839940470087008*a(n-13) +99548995158787584*a(n-14) -8561213583655732224*a(n-15) -1170690303846912000*a(n-16) +100679366130834432000*a(n-17) +3277061542543360000*a(n-18) -281827292658728960000*a(n-19)