A275406 Number of 7Xn 0..2 arrays with no element equal to any value at offset (-2,-1) (-2,0) or (-1,1) and new values introduced in order 0..2.

48, 260, 2645, 27373, 283169, 2940064, 30551417, 317215507, 3295389070, 34229946538, 355557100121, 3693307572143, 38363725298482, 398498904233689, 4139351037446210, 42997002237357820, 446625826073952314

Offset

1,1

Comments

Row 7 of A275401.

Links

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

Formula

Empirical: a(n) = 2*a(n-1) +51*a(n-2) +337*a(n-3) +695*a(n-4) -1387*a(n-5) -17115*a(n-6) -7374*a(n-7) -6423*a(n-8) +162272*a(n-9) -77464*a(n-10) +195500*a(n-11) -502027*a(n-12) +476993*a(n-13) -89619*a(n-14) +690641*a(n-15) -729684*a(n-16) +108400*a(n-17) -61140*a(n-18) +17920*a(n-19) +2032*a(n-20) +1088*a(n-21) for n>22

Example

Some solutions for n=4
..0..0..0..0. .0..0..1..1. .0..0..1..1. .0..1..2..0. .0..0..1..1
..1..2..2..2. .2..2..0..0. .1..2..2..0. .0..0..1..2. .2..0..0..1
..1..1..1..2. .1..2..2..2. .1..1..2..0. .2..2..0..1. .2..1..2..2
..2..0..0..1. .0..1..1..1. .0..0..1..1. .1..1..2..0. .0..1..1..2
..2..2..0..0. .2..0..0..1. .2..2..0..1. .0..1..1..2. .0..0..0..1
..1..1..1..2. .1..2..2..0. .1..1..2..0. .2..2..0..1. .2..2..0..0
..0..0..1..2. .1..1..2..2. .0..1..1..2. .1..2..0..0. .1..2..2..2

Crossrefs

Cf. A275401.

Sequence in context: A223434 A235911 A235904 * A205469 A115056 A001337

Adjacent sequences: A275403 A275404 A275405 * A275407 A275408 A275409

Keyword

nonn

Author

R. H. Hardin, Jul 26 2016

Status

approved