A269888 - OEIS

%I #4 Mar 06 2016 20:07:30

%S 0,6,6,60,432,60,450,11280,11280,450,3000,250992,943488,250992,3000,

%T 18750,5125008,68182800,68182800,5125008,18750,112500,99482544,

%U 4546948272,16086672048,4546948272,99482544,112500,656250,1867222224

%N T(n,k)=Number of nXk 0..5 arrays with some element plus some horizontally, diagonally, antidiagonally or vertically adjacent neighbor totalling five exactly once.

%C Table starts

%C ......0..........6.............60................450...................3000

%C ......6........432..........11280.............250992................5125008

%C .....60......11280.........943488...........68182800.............4546948272

%C ....450.....250992.......68182800........16086672048..........3515869538472

%C ...3000....5125008.....4546948272......3515869538472.......2524680110862912

%C ..18750...99482544...288987039048....733651366146384....1733054018904626400

%C .112500.1867222224.17784013336560.148379658813705408.1153865935196746139616

%H R. H. Hardin, <a href="/A269888/b269888.txt">Table of n, a(n) for n = 1..112</a>

%F Empirical for column k:

%F k=1: a(n) = 10*a(n-1) -25*a(n-2)

%F k=2: a(n) = 30*a(n-1) -197*a(n-2) -420*a(n-3) -196*a(n-4) for n>5

%F k=3: [order 10] for n>11

%F k=4: [order 28] for n>29

%e Some solutions for n=2 k=4

%e ..3..2..0..2. .3..0..2..5. .3..0..4..5. .3..0..1..5. .0..4..2..3

%e ..0..0..0..4. .2..0..1..1. .1..4..4..4. .1..0..0..1. .4..4..0..1

%Y Column 1 is A269760.

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Mar 06 2016