A222387 Sum of neighbor maps: number of 2Xn binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal and antidiagonal neighbors in a random 0..2 2Xn array

4, 16, 48, 248, 1024, 3968, 15872, 65536, 262144, 1048576, 4177632, 16777216, 67108864, 268435456, 1073479680, 4294961152, 17179869184, 68719378432, 274872664064, 1099511627776, 4398046511104, 17592186044416, 70368641459200

Offset

1,1

Comments

Row 2 of A222386

Links

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

Formula

Empirical: a(n) = 4*a(n-1) +32*a(n-4) -128*a(n-5) -256*a(n-8) +1024*a(n-9) +592*a(n-12) -2368*a(n-13) -18944*a(n-16) +75776*a(n-17) +151552*a(n-20) -606208*a(n-21) -109056*a(n-24) +436224*a(n-25) +3489792*a(n-28) -13959168*a(n-29) -27918336*a(n-32) +111673344*a(n-33) +6594560*a(n-36) -26378240*a(n-37) -211025920*a(n-40) +844103680*a(n-41) +1688207360*a(n-44) -6752829440*a(n-45) -189071360*a(n-48) +756285440*a(n-49) +6050283520*a(n-52) -24201134080*a(n-53) -48402268160*a(n-56) +193609072640*a(n-57) +2853175296*a(n-60) -11412701184*a(n-61) -91301609472*a(n-64) +365206437888*a(n-65) +730412875776*a(n-68) -2921651503104*a(n-69) -22011707392*a(n-72) +88046829568*a(n-73) +704374636544*a(n-76) -2817498546176*a(n-77) -5634997092352*a(n-80) +22539988369408*a(n-81) +68719476736*a(n-84) -274877906944*a(n-85) -2199023255552*a(n-88) +8796093022208*a(n-89) +17592186044416*a(n-92) -70368744177664*a(n-93)

Example

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

Crossrefs

Sequence in context: A034918 A119003 A220329 * A366608 A222936 A370019

Adjacent sequences: A222384 A222385 A222386 * A222388 A222389 A222390

Keyword

nonn

Author

R. H. Hardin Feb 18 2013

Status

approved