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 A158841 Triangle read by rows, matrix product of A145677 * A004736. 2
 1, 3, 1, 7, 4, 2, 13, 9, 6, 3, 21, 16, 12, 8, 4, 31, 25, 20, 15, 10, 5, 43, 36, 30, 24, 18, 12, 6, 57, 49, 42, 35, 28, 21, 14, 7, 73, 64, 56, 48, 40, 32, 24, 16, 8, 91, 81, 72, 63, 54, 45, 36, 27, 18, 9 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA T(n,k) = Sum_{j=k..n} A145677(n-1,j-1)*A004736(j,k), assuming column enumeration k >= 1 in A004736. - R. J. Mathar, Nov 05 2011 EXAMPLE First few rows of the triangle:     1;     3,   1;     7,   4,   2;    13,   9,   6,   3;    21,  16,  12,   8,   4;    31,  25,  20,  15,  10,  5;    43,  36,  30,  24,  18, 12,  6;    57,  49,  42,  35,  28, 21, 14,  7;    73,  64,  56,  48,  40, 32, 24, 16,  8;    91,  81,  72,  63,  54, 45, 36, 27, 18,  9;   111, 100,  90,  80,  70, 60, 50, 40, 30, 20, 10;   133, 121, 110,  99,  88, 77, 66, 55, 44, 33, 22, 11;   157, 144, 132, 120, 108, 96, 84, 72, 60, 48, 36, 24, 12;   ... MAPLE A145677 := proc(n, k)         if n <0 or k < 0 or k > n then                 0;         elif k = 0 then                 1;         elif k = n then                 n ;         else                 0 ;         end if; end proc: A004736 := proc(n, k)         if n <0 or k < 1 or k > n then                 0;         else                 n-k+1 ;         end if; end proc: A158841 := proc(n, k)         add( A145677(n-1, j-1)*A004736(j, k), j=k..n) ; end proc: # R. J. Mathar, Nov 05 2011 CROSSREFS Cf. A145677, A002061 (column k=1), A158842 (row sums). Sequence in context: A286513 A193970 A274510 * A213576 A021319 A190177 Adjacent sequences:  A158838 A158839 A158840 * A158842 A158843 A158844 KEYWORD nonn,tabl,easy AUTHOR Gary W. Adamson and Roger L. Bagula, Mar 28 2009 STATUS approved

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Last modified May 24 18:12 EDT 2022. Contains 354043 sequences. (Running on oeis4.)