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A265994 Number of 4Xn integer arrays with each element equal to the number of horizontal and antidiagonal neighbors not equal to itself. 1
1, 1, 10, 2, 2, 4, 24, 15, 47, 68, 112, 196, 281, 672, 1284, 2333, 3974, 7237, 13747, 26006, 48547, 88889, 163918, 302093, 565077, 1052681, 1959261, 3630280, 6723421, 12508832, 23241548, 43276190, 80376902, 149358617, 277502772, 515680095 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Row 4 of A265991.

LINKS

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

FORMULA

Empirical: a(n) = a(n-1) +7*a(n-3) +5*a(n-5) -22*a(n-6) -3*a(n-7) -61*a(n-8) +12*a(n-9) -94*a(n-10) +142*a(n-11) -6*a(n-12) +416*a(n-13) -57*a(n-14) +437*a(n-15) -397*a(n-16) +608*a(n-17) -638*a(n-18) +340*a(n-19) -1686*a(n-20) -458*a(n-21) -1832*a(n-22) +322*a(n-23) -2118*a(n-24) +188*a(n-25) -2933*a(n-26) +2653*a(n-27) +1339*a(n-28) +4226*a(n-29) +1565*a(n-30) +595*a(n-31) +4368*a(n-32) +9027*a(n-33) +5834*a(n-34) +5121*a(n-35) -3877*a(n-36) +2320*a(n-37) +18206*a(n-38) -1742*a(n-39) +9062*a(n-40) -28482*a(n-41) +16363*a(n-42) +9087*a(n-43) +13658*a(n-44) -32807*a(n-45) -3556*a(n-46) -23859*a(n-47) +66076*a(n-48) -51847*a(n-49) -3652*a(n-50) -32067*a(n-51) +21012*a(n-52) +33259*a(n-53) -43932*a(n-54) -15937*a(n-55) +6827*a(n-56) +23414*a(n-57) -1642*a(n-58) -716*a(n-59) -46906*a(n-60) +85736*a(n-61) -72650*a(n-62) +49332*a(n-63) -27086*a(n-64) +8894*a(n-65) +14552*a(n-66) -30512*a(n-67) +30396*a(n-68) -17712*a(n-69) +3888*a(n-70) for n>75

EXAMPLE

Some solutions for n=7

..1..3..2..2..1..1..2....1..3..2..2..1..1..2....1..3..1..1..3..1..1

..2..4..3..1..1..4..1....2..3..3..1..1..3..1....1..1..1..1..1..4..1

..2..3..1..1..1..1..2....1..1..1..1..3..1..1....2..4..1..1..1..1..2

..1..1..3..1..1..3..1....1..3..1..1..1..3..1....1..1..3..1..1..3..1

CROSSREFS

Cf. A265991.

Sequence in context: A259712 A136712 A138999 * A201278 A232589 A010175

Adjacent sequences:  A265991 A265992 A265993 * A265995 A265996 A265997

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 19 2015

STATUS

approved

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Last modified April 4 08:58 EDT 2020. Contains 333213 sequences. (Running on oeis4.)