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 A088972 Triangle read by rows: colored polyominoes. For n >= 1, 1 <= k <= n, T(n, k) is the number of k-colored n-celled polyominoes, counted up to rotation, reflection and permutation of the colors. Adjacent cells must be different colors. T(n, k) counts only polyominoes that include all k colors. 0
 1, 0, 1, 0, 2, 2, 0, 5, 10, 5, 0, 12, 66, 55, 12, 0, 35, 415, 695, 285, 35, 0, 108, 2844, 8227, 6080, 1446, 108, 0, 369, 19875, 95697, 113418, 46441, 7140, 369, 0, 1285, 142046, 1092358, 1964647, 1238196, 320074, 34385, 1285, 0, 4655, 1026197, 12351464 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS For n > 1, T(n, 2) = T(n, n) = A000105(n). LINKS D. Wasserman, Illustrations of colored pentominoes and hexominoes EXAMPLE RBRG is considered the same as BRBG, but different from RBGR. 1; 0,1; 0,2,2; 0,5,10,5; ... PROG See the link for MATLAB code. CROSSREFS Cf. A000105. Sequence in context: A329687 A321127 A222128 * A168505 A100334 A277295 Adjacent sequences:  A088969 A088970 A088971 * A088973 A088974 A088975 KEYWORD nonn,tabl,less AUTHOR David Wasserman, Oct 30 2003 STATUS approved

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Last modified September 20 11:42 EDT 2021. Contains 347584 sequences. (Running on oeis4.)