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 A204560 Symmetric matrix: f(i,j)=floor[(2i+2j+4)/4]-floor[(i+j+2)/4], by (constant) antidiagonals. 3
 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS For n>=2, the number of occurrences of n is 16n-14.  For a guide to related sequences and permanents, see A204551. Northwest corner: 1 1 2 2 2 2 3 3 3 1 2 2 2 2 3 3 3 3 2 2 2 2 3 3 3 3 4 2 2 2 3 3 3 3 4 4 2 3 3 3 3 4 4 4 4 3 3 3 3 4 4 4 4 5 3 3 3 4 4 4 4 5 5 f[i_, j_] := Floor[(2 i + 2 j + 4)/4] - Floor[(i + j + 2)/4]; m[n_] := Table[f[i, j], {i, 1, n}, {j, 1, n}] TableForm[m[8]] (* 8x8 principal submatrix *) Flatten[Table[f[i, n + 1 - i],   {n, 1, 14}, {i, 1, n}]]     (* A204560 *) Permanent[m_] :=   With[{a = Array[x, Length[m]]},    Coefficient[Times @@ (m.a), Times @@ a]]; Table[Permanent[m[n]], {n, 1, 15}]  (* A204561 *) Cf. A204561, A204551. tabl LINKS CROSSREFS Sequence in context: A176170 A062153 A217693 * A135661 A082998 A076620 Adjacent sequences:  A204557 A204558 A204559 * A204561 A204562 A204563 KEYWORD nonn,tabl AUTHOR Clark Kimberling, Jan 16 2012 STATUS approved

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Last modified December 16 06:18 EST 2019. Contains 330016 sequences. (Running on oeis4.)