login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A252509 Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 2 5 6 or 7 1

%I

%S 2055,3980,11476,28877,83016,252551,767176,2326656,7067545,21555438,

%T 65998872,202139805,619664176,1902757710,5844530563,17960909526,

%U 55236099834,169893963331,522684802558,1608599668122,4950903773021

%N Number of (n+2)X(3+2) 0..3 arrays with every 3X3 subblock row and column sum equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum not equal to 0 2 5 6 or 7

%C Column 3 of A252514

%H R. H. Hardin, <a href="/A252509/b252509.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 3*a(n-1) -a(n-2) +35*a(n-3) -93*a(n-4) +31*a(n-5) -442*a(n-6) +939*a(n-7) -313*a(n-8) +2607*a(n-9) -3585*a(n-10) +1195*a(n-11) -8743*a(n-12) +6714*a(n-13) -2238*a(n-14) +21413*a(n-15) -14283*a(n-16) +4761*a(n-17) -46814*a(n-18) +26640*a(n-19) -8880*a(n-20) +86138*a(n-21) -23769*a(n-22) +7923*a(n-23) -125344*a(n-24) +19671*a(n-25) -6557*a(n-26) +157146*a(n-27) -12624*a(n-28) +4208*a(n-29) -170762*a(n-30) -16695*a(n-31) +5565*a(n-32) +140413*a(n-33) +53586*a(n-34) -17862*a(n-35) -68838*a(n-36) -37272*a(n-37) +12424*a(n-38) +13448*a(n-39) +768*a(n-40) -256*a(n-41) -256*a(n-42) for n>47

%e Some solutions for n=4

%e ..2..2..2..2..2....3..2..2..2..2....2..3..1..3..2....0..1..1..0..1

%e ..2..3..1..3..2....1..3..1..3..1....2..1..3..1..3....0..1..1..0..1

%e ..3..1..3..1..3....3..1..3..1..3....1..3..1..3..2....2..0..0..2..3

%e ..1..3..1..3..1....2..3..1..3..2....2..1..3..1..2....0..1..1..0..1

%e ..2..1..3..1..3....2..1..3..1..2....2..3..1..3..2....3..1..1..0..1

%e ..2..2..1..3..1....1..3..1..2..2....3..1..3..1..3....2..0..0..2..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 18 2014

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 18 19:51 EDT 2022. Contains 353824 sequences. (Running on oeis4.)