A204035 Number of (n+1)X5 0..1 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards

286, 1758, 10505, 44366, 189580, 642272, 2198077, 6415866, 18855400, 49463034, 130378965, 316145840, 769485458, 1759764220, 4037835608, 8842012560, 19423451542, 41206754874, 87691553223, 181894892784, 378439038413

Offset

1,1

Comments

Column 4 of A204039

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +26*a(n-2) -122*a(n-3) -302*a(n-4) +1766*a(n-5) +1978*a(n-6) -16138*a(n-7) -6930*a(n-8) +104454*a(n-9) +210*a(n-10) -509250*a(n-11) +151130*a(n-12) +1941310*a(n-13) -1020190*a(n-14) -5928050*a(n-15) +4236940*a(n-16) +14732870*a(n-17) -13009090*a(n-18) -30101870*a(n-19) +31422886*a(n-20) +50835986*a(n-21) -61498066*a(n-22) -71033438*a(n-23) +99090082*a(n-24) +81802994*a(n-25) -132597178*a(n-26) -76806422*a(n-27) +147941950*a(n-28) +57458666*a(n-29) -137661898*a(n-30) -32529638*a(n-31) +106500613*a(n-32) +11969534*a(n-33) -68049136*a(n-34) -652352*a(n-35) +35523824*a(n-36) -2735264*a(n-37) -14904960*a(n-38) +2248512*a(n-39) +4904928*a(n-40) -1052352*a(n-41) -1219328*a(n-42) +329216*a(n-43) +215296*a(n-44) -68608*a(n-45) -24064*a(n-46) +8704*a(n-47) +1280*a(n-48) -512*a(n-49)

Example

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

Crossrefs

Sequence in context: A329392 A253322 A241616 * A235409 A238251 A027798

Adjacent sequences: A204032 A204033 A204034 * A204036 A204037 A204038

Keyword

nonn

Author

R. H. Hardin Jan 09 2012

Status

approved