A204834 Number of (n+1)X3 0..2 arrays with the permanents of all 2X2 subblocks equal and nonzero

132, 524, 1616, 6370, 21380, 81706, 284982, 1068556, 3806698, 14134062, 50991492, 188455830, 685297032, 2528016622, 9240734242, 34073187134, 124993402790, 461002644276, 1695445551856, 6256762635894, 23054254621028, 85137162675964

Offset

1,1

Comments

Column 2 of A204840

Links

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

Formula

Empirical: a(n) = 7*a(n-1) +27*a(n-2) -272*a(n-3) -166*a(n-4) +4400*a(n-5) -2099*a(n-6) -38451*a(n-7) +40394*a(n-8) +197193*a(n-9) -288743*a(n-10) -602214*a(n-11) +1139080*a(n-12) +1038852*a(n-13) -2693225*a(n-14) -762225*a(n-15) +3842539*a(n-16) -401148*a(n-17) -3143804*a(n-18) +1172882*a(n-19) +1265630*a(n-20) -763476*a(n-21) -143344*a(n-22) +155436*a(n-23) -12496*a(n-24) -5304*a(n-25) +528*a(n-26)

Example

Some solutions for n=4
..2..2..2....2..1..0....2..2..1....2..2..2....1..2..1....0..1..0....2..0..2
..1..0..1....2..0..2....0..2..1....0..2..0....1..1..1....2..2..2....0..2..2
..0..2..1....1..1..1....2..2..1....2..0..2....2..1..2....0..1..0....2..0..2
..1..0..1....1..1..1....2..0..2....1..2..2....1..1..1....2..2..2....1..2..2
..0..2..2....2..0..2....0..2..1....1..2..0....1..2..1....0..1..0....2..0..2

Crossrefs

Sequence in context: A248555 A253502 A257105 * A241288 A115132 A158543

Adjacent sequences: A204831 A204832 A204833 * A204835 A204836 A204837

Keyword

nonn

Author

R. H. Hardin Jan 19 2012

Status

approved