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A303018 Number of 4Xn 0..1 arrays with every element equal to 0, 1, 2, 4 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero. 1
8, 81, 308, 1047, 4237, 18513, 79945, 344190, 1508465, 6674176, 29600788, 131609799, 587110082, 2625016947, 11752855152, 52678292451, 236333170151, 1061002713735, 4765681686396, 21414073733214, 96250281021248 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A303016.

LINKS

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

FORMULA

Empirical: a(n) = 13*a(n-1) -43*a(n-2) -114*a(n-3) +905*a(n-4) -716*a(n-5) -4942*a(n-6) +10512*a(n-7) -1274*a(n-8) -24667*a(n-9) +113391*a(n-10) -131084*a(n-11) -520308*a(n-12) +893085*a(n-13) +1333985*a(n-14) -2021387*a(n-15) -2578350*a(n-16) +1351025*a(n-17) +3392056*a(n-18) +2205994*a(n-19) +738207*a(n-20) -2427773*a(n-21) -12766075*a(n-22) -8590205*a(n-23) +17172441*a(n-24) +17940243*a(n-25) +6296475*a(n-26) +4917056*a(n-27) -32041874*a(n-28) -45463888*a(n-29) +15025779*a(n-30) +31754810*a(n-31) +12278275*a(n-32) +37820834*a(n-33) +9133429*a(n-34) -61487855*a(n-35) -35332780*a(n-36) +17109050*a(n-37) +9603961*a(n-38) +6992417*a(n-39) +20256250*a(n-40) +8676894*a(n-41) -14367124*a(n-42) -14312869*a(n-43) +3565874*a(n-44) +5337628*a(n-45) -3565536*a(n-46) -953845*a(n-47) +2949481*a(n-48) +762004*a(n-49) -485196*a(n-50) -514434*a(n-51) -229910*a(n-52) +231676*a(n-53) -3016*a(n-54) -119908*a(n-55) +43584*a(n-56) +52224*a(n-57) -7408*a(n-58) -4672*a(n-59) -1024*a(n-60) -2048*a(n-61) +768*a(n-62) for n>64

EXAMPLE

Some solutions for n=5

..0..1..0..0..0. .0..0..0..1..0. .0..0..1..0..1. .0..1..0..1..1

..0..0..0..1..0. .0..1..0..1..0. .1..0..1..1..1. .0..0..0..0..1

..0..1..0..1..0. .0..1..0..1..1. .1..1..0..0..0. .1..0..1..0..1

..0..1..1..1..0. .1..1..0..0..1. .0..0..1..0..1. .1..0..1..0..1

CROSSREFS

Cf. A303016.

Sequence in context: A227227 A303184 A302325 * A247536 A302822 A303515

Adjacent sequences:  A303015 A303016 A303017 * A303019 A303020 A303021

KEYWORD

nonn

AUTHOR

R. H. Hardin, Apr 17 2018

STATUS

approved

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Last modified November 27 07:28 EST 2021. Contains 349365 sequences. (Running on oeis4.)