A303042 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 3, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.

8, 10, 35, 74, 234, 869, 2926, 8500, 27931, 96592, 325288, 1051261, 3506796, 11931140, 40248675, 134258666, 451774036, 1530339997, 5170509004, 17416735952, 58815737695, 199037081262, 673067713068, 2274228205231, 7690132113108

Offset

1,1

Comments

Row 4 of A303040.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +4*a(n-2) -6*a(n-3) +73*a(n-4) -240*a(n-5) -341*a(n-6) +480*a(n-7) -2065*a(n-8) +7402*a(n-9) +10592*a(n-10) -13225*a(n-11) +34742*a(n-12) -123483*a(n-13) -182747*a(n-14) +195467*a(n-15) -385754*a(n-16) +1222527*a(n-17) +1964345*a(n-18) -1804329*a(n-19) +2869079*a(n-20) -7219556*a(n-21) -13753473*a(n-22) +10685789*a(n-23) -13899268*a(n-24) +23713166*a(n-25) +62811529*a(n-26) -38417170*a(n-27) +40787608*a(n-28) -30283629*a(n-29) -175703207*a(n-30) +73169804*a(n-31) -64635290*a(n-32) -46685202*a(n-33) +254565055*a(n-34) -64087923*a(n-35) +48130794*a(n-36) +186503318*a(n-37) -110678378*a(n-38) +80503265*a(n-39) +10154339*a(n-40) -180320138*a(n-41) -40411189*a(n-42) -123008803*a(n-43) -84599828*a(n-44) +51373230*a(n-45) +938426*a(n-46) +4023387*a(n-47) +14582167*a(n-48) -4415294*a(n-49) +1720928*a(n-50) -285856*a(n-51) +1699116*a(n-52) +701304*a(n-53) -579560*a(n-54) +490896*a(n-55) -345696*a(n-56) -44480*a(n-57) +34144*a(n-58) -47104*a(n-59) +18304*a(n-60) -2048*a(n-61) for n>62

Example

Some solutions for n=5
..0..1..0..1..0. .0..1..1..1..0. .0..1..0..0..1. .0..1..0..0..1
..1..1..0..1..1. .1..1..1..1..1. .0..1..1..1..1. .0..1..0..1..0
..0..1..0..1..0. .0..1..1..1..0. .0..1..0..0..0. .0..1..0..1..0
..0..1..0..0..0. .0..1..0..1..0. .0..1..0..1..1. .1..0..0..1..0

Crossrefs

Cf. A303040.

Sequence in context: A223587 A302312 A245199 * A242506 A302879 A303527

Adjacent sequences: A303039 A303040 A303041 * A303043 A303044 A303045

Keyword

nonn

Author

R. H. Hardin, Apr 17 2018

Status

approved