A234708 Number of (n+1) X (4+1) 0..7 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 6 (constant-stress 1 X 1 tilings).

47306, 127586, 334938, 1108418, 3530906, 13445762, 48741018, 204403250, 809806586, 3649630466, 15448766778, 73732987538, 328732631066, 1644074979362, 7638831660378, 39686386752050, 190506531532346, 1020461790949826

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..77

Formula

Empirical: a(n) = 13*a(n-1) +163*a(n-2) -2779*a(n-3) -9420*a(n-4) +268200*a(n-5) +60770*a(n-6) -15439130*a(n-7) +22995763*a(n-8) +589369361*a(n-9) -1588530069*a(n-10) -15656100243*a(n-11) +58787313370*a(n-12) +294085396250*a(n-13) -1450484076640*a(n-14) -3845621898440*a(n-15) +25550700910752*a(n-16) +32289252593664*a(n-17) -330371143423376*a(n-18) -113428722066352*a(n-19) +3163397610252320*a(n-20) -1019517140684000*a(n-21) -22338341568842880*a(n-22) +18872130722296320*a(n-23) +114348342295028736*a(n-24) -148610586143628288*a(n-25) -409381709070163968*a(n-26) +722386331480346624*a(n-27) +952125730341396480*a(n-28) -2277950012653363200*a(n-29) -1180887662923776000*a(n-30) +4529957329207296000*a(n-31) +69777190748160000*a(n-32) -5142605210910720000*a(n-33) +1663475920404480000*a(n-34) +2524921315983360000*a(n-35) -1415843728588800000*a(n-36).

Example

Some solutions for n=2:
  3 6 0 6 0      4 7 5 7 6      6 0 3 7 7      2 2 2 1 4
  4 1 1 1 1      4 1 5 1 6      5 5 2 0 6      0 6 0 5 2
  3 6 0 6 0      4 7 5 7 6      6 0 3 7 7      1 1 1 0 3

Crossrefs

Column 4 of A234712.

Sequence in context: A218097 A293584 A263067 * A069370 A241221 A261339

Adjacent sequences: A234705 A234706 A234707 * A234709 A234710 A234711

Keyword

nonn

Author

R. H. Hardin, Dec 29 2013

Status

approved