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A250556
Number of length n+2 0..3 arrays with the sum of second differences multiplied by some arrangement of +-1 equal to zero.
1
8, 60, 302, 1516, 7126, 30780, 127586, 518052, 2085808, 8367220, 33513408, 134137736, 536713774, 2147172564, 8589316642, 34358507208, 137436497326, 549750908948, 2199013454674, 8796073430888, 35184332920270, 140737410034420
OFFSET
1,1
COMMENTS
Column 3 of A250561.
LINKS
Manuel Kauers and Christoph Koutschan, Table of n, a(n) for n = 1..1000 (terms 1..47 from R. H. Hardin).
M. Kauers and C. Koutschan, Some D-finite and some possibly D-finite sequences in the OEIS, arXiv:2303.02793 [cs.SC], 2023.
FORMULA
From Manuel Kauers and Christoph Koutschan, Mar 01 2023: (Start)
Generating function: 2*x*(4 + 2*x - 3*x^2 + 73*x^3 + 115*x^4 - 139*x^5 - 453*x^6 - 1231*x^7 + 38*x^8 + 406*x^9 + 3597*x^10 + 2087*x^11 + 1666*x^12 - 3614*x^13 - 4178*x^14 - 4504*x^15 + 903*x^16 + 1985*x^17 + 4173*x^18 + 403*x^19 - 202*x^20 - 1324*x^21 - 1296*x^22 + 684*x^23 - 300*x^24 + 508*x^25 - 56*x^26 + 32*x^27)/((1 - 4*x)*(1 - 2*x)*(1 - x)^3*(1 + x)^2*(1 + x^2)^2*(1 - 2*x^3)^2).
Recurrence equation: 32*a(n) - 56*a(n + 1) + 28*a(n + 2) - 36*a(n + 3) - 8*a(n + 4) + 84*a(n + 5) - 44*a(n + 6) + 58*a(n + 7) - 73*a(n + 8) - a(n + 9) + 4*a(n + 10) - 8*a(n + 11) + 42*a(n + 12) - 26*a(n + 13) + 12*a(n + 14) - 14*a(n + 15) + 7*a(n + 16) - a(n + 17) = 0 for n>11. (End)
EXAMPLE
Some solutions for n=6
3 1 1 0 3 3 3 1 1 1 3 0 1 2 0 2
2 2 0 0 0 3 0 0 0 2 3 3 1 2 1 2
3 2 2 1 2 1 0 2 1 2 2 2 3 1 1 2
2 2 2 3 0 1 0 3 1 2 0 1 3 3 3 0
1 0 1 2 1 3 1 3 2 2 0 2 1 3 1 1
0 3 0 1 1 2 3 3 0 2 0 1 3 3 0 2
3 1 2 0 3 3 3 0 2 1 3 1 0 0 3 2
2 0 3 0 0 1 0 3 1 2 3 2 2 0 0 2
CROSSREFS
Sequence in context: A199906 A297690 A268599 * A054401 A159727 A081158
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 25 2014
STATUS
approved