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A323970
Number of 6 X n integer matrices (m_{i,j}) such that m_{1,1}=0, m_{6,n}=2, and all rows, columns, and falling diagonals are (weakly) monotonic without jumps of 2.
2
1, 10, 85, 632, 3423, 14795, 54219, 174844, 508484, 1357051, 3367166, 7846507, 17311702, 36401032, 73344164, 142259423, 266651159, 484610624, 856389171, 1475218962, 2482510921, 4088870385, 6602746625, 10468982846, 16320069070, 25043533065, 37869646820
OFFSET
0,2
LINKS
FORMULA
G.f.: -(4*x^13 -47*x^12 +253*x^11 -822*x^10 +1788*x^9 -2728*x^8 +2958*x^7 -2253*x^6 +1145*x^5 -308*x^4 +21*x^3 +33*x^2 -3*x+1) / (x-1)^13.
CROSSREFS
Row (or column) 6 of array in A323846.
Sequence in context: A104128 A345895 A014341 * A253009 A291389 A081903
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Feb 09 2019
STATUS
approved