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!)
A254561 Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of the four sums of the central row, central column, diagonal and antidiagonal nondecreasing horizontally and vertically 1

%I

%S 512,2384,10240,37200,116056,358324,1029664,2800912,7536024,19539824,

%T 49071028,122137716,297265144,708589765,1676189792,3907023789,

%U 8978272228,20497994769,46321914076,103638618227,230617227832,509410016859

%N Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of the four sums of the central row, central column, diagonal and antidiagonal nondecreasing horizontally and vertically

%C Column 1 of A254568

%H R. H. Hardin, <a href="/A254561/b254561.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) -12*a(n-2) +38*a(n-3) -183*a(n-4) +372*a(n-5) -654*a(n-6) +2508*a(n-7) -5208*a(n-8) +6760*a(n-9) -20358*a(n-10) +43512*a(n-11) -46889*a(n-12) +108378*a(n-13) -241308*a(n-14) +230802*a(n-15) -393975*a(n-16) +933156*a(n-17) -830560*a(n-18) +975804*a(n-19) -2563392*a(n-20) +2214488*a(n-21) -1532964*a(n-22) +4959408*a(n-23) -4373184*a(n-24) +1014144*a(n-25) -6401472*a(n-26) +6289888*a(n-27) +1572336*a(n-28) +4429248*a(n-29) -6288128*a(n-30) -5389632*a(n-31) +990720*a(n-32) +3815040*a(n-33) +7654464*a(n-34) -6015744*a(n-35) -567040*a(n-36) -6564864*a(n-37) +6844416*a(n-38) -1196032*a(n-39) +3508224*a(n-40) -4153344*a(n-41) +1105920*a(n-42) -1081344*a(n-43) +1376256*a(n-44) -425984*a(n-45) +147456*a(n-46) -196608*a(n-47) +65536*a(n-48) for n>50

%e Some solutions for n=4

%e ..1..0..1....1..0..0....0..1..0....0..1..0....1..1..0....1..0..1....1..1..0

%e ..1..0..1....0..0..0....1..0..0....0..0..1....1..0..0....1..0..1....0..0..0

%e ..0..1..1....1..0..0....1..0..0....1..1..1....1..0..0....0..0..1....1..0..1

%e ..1..1..0....1..0..0....1..0..1....1..1..0....1..1..0....1..0..1....1..0..1

%e ..0..1..1....1..0..0....1..0..0....1..1..1....1..1..1....1..1..0....1..0..0

%e ..1..0..1....0..0..1....1..1..1....1..1..1....1..0..1....1..1..0....1..1..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Feb 01 2015

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 August 1 17:43 EDT 2021. Contains 346402 sequences. (Running on oeis4.)