login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A252408 Number of (1+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7 1
458, 661, 983, 1551, 2689, 4582, 7662, 13777, 24375, 41464, 75533, 136287, 235164, 430077, 781216, 1360689, 2491499, 4538408, 7962706, 14582736, 26596620, 46939611, 85931062, 156803960, 278103939, 508821117, 928615419, 1653829878 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 1 of A252407

LINKS

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

FORMULA

Empirical: a(n) = 24*a(n-3) +2*a(n-4) +2*a(n-5) -238*a(n-6) -43*a(n-7) -38*a(n-8) +1250*a(n-9) +371*a(n-10) +276*a(n-11) -3646*a(n-12) -1614*a(n-13) -881*a(n-14) +5273*a(n-15) +3512*a(n-16) +544*a(n-17) -844*a(n-18) -2417*a(n-19) +4295*a(n-20) -7725*a(n-21) -4205*a(n-22) -11851*a(n-23) +6943*a(n-24) +7702*a(n-25) +7854*a(n-26) +3635*a(n-27) -338*a(n-28) +12310*a(n-29) -4031*a(n-30) -4268*a(n-31) -20898*a(n-32) -4562*a(n-33) -2569*a(n-34) -470*a(n-35) +116*a(n-36) +4313*a(n-37) +20348*a(n-38) +9039*a(n-39) +1549*a(n-40) -10234*a(n-41) -2364*a(n-42) -2756*a(n-43) -10136*a(n-44) -8113*a(n-45) +3573*a(n-46) +15837*a(n-47) +7994*a(n-48) -3971*a(n-49) -7737*a(n-50) -4018*a(n-51) -2546*a(n-52) -4164*a(n-53) -235*a(n-54) +6544*a(n-55) +9225*a(n-56) +4319*a(n-57) -1802*a(n-58) -4116*a(n-59) -3926*a(n-60) -2982*a(n-61) -1660*a(n-62) +1107*a(n-63) +2613*a(n-64) +1886*a(n-65) +96*a(n-66) -572*a(n-67) -332*a(n-68) -189*a(n-69) -176*a(n-70) -36*a(n-71) +136*a(n-72) +68*a(n-73) -40*a(n-74) -40*a(n-75) +16*a(n-76) +16*a(n-77) -4*a(n-79) for n>86

EXAMPLE

Some solutions for n=4

..2..2..0..2..2..3....0..3..3..1..3..0....1..0..2..2..0..2....2..2..3..2..2..0

..1..3..3..1..0..1....0..2..1..1..2..1....2..1..3..0..0..2....1..0..3..1..3..3

..2..0..2..2..3..1....0..3..1..3..3..0....2..0..0..3..0..1....2..3..2..2..0..2

CROSSREFS

Sequence in context: A252400 A252399 A252407 * A251474 A251468 A286845

Adjacent sequences:  A252405 A252406 A252407 * A252409 A252410 A252411

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 17 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 31 19:00 EDT 2020. Contains 338111 sequences. (Running on oeis4.)