A252644 Number of (4+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 3 4 6 or 7

2230, 10259, 39492, 95904, 448323, 1848350, 4416767, 21690676, 92632549, 215263202, 1102681029, 4817209197, 10969594133, 57815579003, 256126895043, 575854261780, 3089052609134, 13798462237870, 30788679240521

Offset

1,1

Comments

Row 4 of A252640

Links

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

Formula

Empirical: a(n) = 150*a(n-3) -8737*a(n-6) +259868*a(n-9) -4430048*a(n-12) +47350454*a(n-15) -340156437*a(n-18) +1738274612*a(n-21) -6622942497*a(n-24) +19454338570*a(n-27) -44675220248*a(n-30) +79646734248*a(n-33) -107698827864*a(n-36) +107079631646*a(n-39) -75929658840*a(n-42) +37409311284*a(n-45) -12501763424*a(n-48) +2743088704*a(n-51) -371898368*a(n-54) +27607040*a(n-57) -819200*a(n-60) for n>62

Example

Some solutions for n=4
..2..1..1..2..1..1....1..1..2..1..1..2....2..3..2..2..3..2....2..2..0..2..2..0
..0..1..3..3..1..0....1..3..3..1..0..3....3..0..1..3..0..1....1..0..3..1..3..3
..0..3..1..0..3..1....3..1..0..3..1..3....0..2..2..3..2..2....2..0..2..2..3..2
..2..1..1..2..1..1....1..1..2..1..1..2....2..3..2..2..0..2....2..2..3..2..2..3
..3..1..3..0..1..3....1..0..3..1..3..3....0..3..1..0..3..1....1..0..3..1..3..3
..0..3..1..3..3..1....3..1..3..0..1..3....3..2..2..3..2..2....2..3..2..2..0..2

Crossrefs

Sequence in context: A205225 A236496 A208181 * A205046 A205039 A205981

Adjacent sequences: A252641 A252642 A252643 * A252645 A252646 A252647

Keyword

nonn

Author

R. H. Hardin, Dec 19 2014

Status

approved