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A266025 T(n,k)=Number of nXk integer arrays with each element equal to the number of horizontal, vertical and antidiagonal neighbors exactly one smaller than itself. 8

%I #4 Dec 20 2015 07:13:11

%S 1,3,3,4,7,4,5,14,14,5,9,42,33,42,9,16,99,91,91,99,16,25,259,316,577,

%T 316,259,25,39,719,1045,3796,3796,1045,719,39,64,1784,3394,19688,

%U 39064,19688,3394,1784,64,105,4792,11102,110924,336357,336357,110924,11102,4792,105

%N T(n,k)=Number of nXk integer arrays with each element equal to the number of horizontal, vertical and antidiagonal neighbors exactly one smaller than itself.

%C Table starts

%C ...1.....3......4........5..........9...........16...........25............39

%C ...3.....7.....14.......42.........99..........259..........719..........1784

%C ...4....14.....33.......91........316.........1045.........3394.........11102

%C ...5....42.....91......577.......3796........19688.......110924........656555

%C ...9....99....316.....3796......39064.......336357......3254726......31035211

%C ..16...259...1045....19688.....336357......4285397.....63460724.....950319651

%C ..25...719...3394...110924....3254726.....63460724...1577145547...38948760562

%C ..39..1784..11102...656555...31035211....950319651..38948760562.1561479265416

%C ..64..4792..36842..3732300..292685424..13831198142.916245375526

%C .105.12479.122052.21344656.2799525337.203362718849

%H R. H. Hardin, <a href="/A266025/b266025.txt">Table of n, a(n) for n = 1..127</a>

%F Empirical for column k:

%F k=1: a(n) = a(n-1) +a(n-3) +a(n-4)

%F k=2: [order 21]

%F k=3: [order 94] for n>95

%e Some solutions for n=4 k=4

%e ..1..0..0..1....0..1..2..1....0..1..1..0....0..0..1..2....1..0..1..2

%e ..1..2..3..2....1..3..2..0....2..1..1..1....0..2..2..1....1..1..3..1

%e ..1..2..3..1....2..1..2..0....0..1..1..1....1..2..0..2....2..2..2..0

%e ..0..1..2..0....0..2..1..1....2..1..0..1....1..0..0..1....0..1..2..1

%Y Column 1 is A195971.

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Dec 20 2015

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Last modified March 29 09:59 EDT 2024. Contains 371268 sequences. (Running on oeis4.)