cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A264947 Number of 4 X n arrays containing n copies of 0..4-1 with no equal horizontal neighbors and new values introduced sequentially from 0.

Original entry on oeis.org

1, 60, 3201, 184740, 11375145, 730983420, 48402531561, 3282992503164, 226854309720993, 15915758107113276, 1130694005695927761, 81177583723495750340, 5880587303767912833417, 429300706847441007321756
Offset: 1

Views

Author

R. H. Hardin, Nov 29 2015

Keywords

Comments

Row 4 of A264945.

Examples

			Some solutions for n=4:
  0 1 0 2   0 1 2 0   0 1 2 0   0 1 0 1   0 1 2 0
  2 0 3 1   3 0 1 2   0 3 1 3   0 2 3 1   3 1 0 3
  2 3 2 1   3 2 3 1   3 2 0 1   3 1 3 2   2 3 1 2
  1 3 0 3   1 2 3 0   2 1 2 3   2 0 2 3   3 1 0 2
		

Crossrefs

Cf. A264945.

Programs

  • Mathematica
    cols = Tuples[{0, 1, 2, 3}, 4];
    tmat = Table[If[Or @@ MapThread[SameQ, cols[[{i, j}]]], 0, 1], {i, 256}, {j, 256}];
    vec = vvec = ((x^Count[#, 0] * y^Count[#, 1] * z^Count[#, 2]) & /@ cols);
    Prepend[Table[vec = Expand[vvec*(tmat.vec)]; Coefficient[Total[vec], (x*y*z)^n]/24, {n, 2, 10}], 1]