cp's OEIS Frontend

A189440 Number of 8Xn array permutations with each element not moving, or moving one space N, SW or SE.

%I A189440 #7 Jul 22 2025 11:45:15
%S A189440 1,178,4247,151081,4681376,150278792,4742833745,150293731826,
%T A189440 4749894184013,150188217692849,4746661471100000,150023910675120177,
%U A189440 4741289321059094672,149841677173229096314,4735456640427554680211
%N A189440 Number of 8Xn array permutations with each element not moving, or moving one space N, SW or SE.
%C A189440 Row 8 of A189435
%H A189440 R. H. Hardin, <a href="/A189440/b189440.txt">Table of n, a(n) for n = 1..200</a>
%F A189440 Empirical: a(n) = 41*a(n-1) +4*a(n-2) -11620*a(n-3) +36842*a(n-4) +1075370*a(n-5) -2836328*a(n-6) -48309578*a(n-7) +90931538*a(n-8) +1244988774*a(n-9) -1330625788*a(n-10) -20764885728*a(n-11) -807100472*a(n-12) +238887356494*a(n-13) +241073214022*a(n-14) -1547096306562*a(n-15) -2156429020912*a(n-16) +2299948270878*a(n-17) +555225276722*a(n-18) +22196146658772*a(n-19) +35039812353132*a(n-20) -38273112869294*a(n-21) -78128931220886*a(n-22) -66141096694820*a(n-23) -82372827473972*a(n-24) +44882503153426*a(n-25) +213386056389486*a(n-26) -238605737532448*a(n-27) -236154021779002*a(n-28) +243937070936182*a(n-29) -27414905904242*a(n-30) -59027273543752*a(n-31) -6342449715912*a(n-32) -23074078011388*a(n-33) +12249673700910*a(n-34) +2028566638082*a(n-35) +478373441582*a(n-36) -47898668640*a(n-37) -51624561206*a(n-38) +2997662842*a(n-39) +324210628*a(n-40) -114260276*a(n-41) +3563*a(n-42) -12287*a(n-43)
%e A189440 Some solutions for 8X3
%e A189440 ..3..4..2....0..4..5....0..4..5....0..1..5....0..1..5....0..1..2....0..4..2
%e A189440 ..1..0..5....6..2..1....3..2..1....6..2..8....6..2..8....3..7..8....1..7..5
%e A189440 ..6..7..8....9..3..8....6.10.11....4..3.11....9..3..4....6..5..4....9..3..8
%e A189440 ..9.10.11....7.13.14....9..8..7....7.13.14....7.10.14...12.13.11...12..6.11
%e A189440 .15.13.14...12.11.10...12.13.14...12..9.10...12.11.17...15..9.10...10.13.14
%e A189440 .18.12.17...18.19.17...15.16.20...15.16.20...13.19.20...18.14.17...15.19.17
%e A189440 .21.22.16...16.15.20...18.17.23...18.17.23...18.15.16...16.19.20...16.22.20
%e A189440 .19.20.23...21.22.23...21.22.19...21.22.19...21.22.23...21.22.23...21.18.23
%K A189440 nonn
%O A189440 1,2
%A A189440 _R. H. Hardin_ Apr 22 2011