A250938 Number of (n+1)X(4+1) 0..2 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction

2247, 15431, 87529, 444421, 2067987, 8976385, 36809498, 144007880, 541598982, 1969991292, 6964460154, 24028268136, 81182285391, 269383972831, 880117983928, 2837311053260, 9042403815092, 28535164299486, 89292416423582

Offset

1,1

Comments

Column 4 of A250942

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 32*a(n-1) -484*a(n-2) +4602*a(n-3) -30861*a(n-4) +155214*a(n-5) -607776*a(n-6) +1898436*a(n-7) -4807563*a(n-8) +9976284*a(n-9) -17075340*a(n-10) +24182082*a(n-11) -28338375*a(n-12) +27397590*a(n-13) -21713520*a(n-14) +13959072*a(n-15) -7163424*a(n-16) +2864448*a(n-17) -859904*a(n-18) +182272*a(n-19) -24320*a(n-20) +1536*a(n-21) for n>29

Example

Some solutions for n=3
..1..1..0..1..0....1..2..0..0..2....2..1..0..0..1....1..2..1..0..0
..1..1..0..1..0....2..1..1..2..0....1..2..1..1..0....1..2..2..1..1
..2..0..1..0..2....2..2..2..1..1....2..1..2..0..1....1..2..2..1..1
..2..0..1..0..2....2..2..2..1..2....2..1..2..0..1....1..2..2..1..2

Crossrefs

Sequence in context: A107529 A260608 A125522 * A230679 A236114 A184767

Adjacent sequences: A250935 A250936 A250937 * A250939 A250940 A250941

Keyword

nonn

Author

R. H. Hardin, Nov 28 2014

Status

approved