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 A108359 A symmetric number triangle based on floor((n+2)/2). 4
 1, 1, 1, 1, 3, 1, 1, 5, 5, 1, 1, 7, 14, 7, 1, 1, 9, 28, 28, 9, 1, 1, 11, 47, 76, 47, 11, 1, 1, 13, 71, 163, 163, 71, 13, 1, 1, 15, 100, 301, 433, 301, 100, 15, 1, 1, 17, 134, 502, 961, 961, 502, 134, 17, 1, 1, 19, 173, 778, 1879, 2515, 1879, 778, 173, 19, 1, 1, 21, 217, 1141 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS Row sums are A108360. Diagonal sums are A108361. LINKS FORMULA Number triangle T(n,k) = Sum_{j=0..n-k} binomial(k,j)*binomial(n-j,k)*floor((j+2)/2). As a square array read by antidiagonals, T(n,k) = Sum_{j=0..n} binomial(k,j)*binomial(n+k-j,k)*floor((j+2)/2). EXAMPLE Rows begin   1;   1,  1;   1,  3,  1;   1,  5,  5,  1;   1,  7, 14,  7,  1;   1,  9, 28, 28,  9,  1;   1, 11, 47, 76, 47, 11,  1; As a square array read by antidiagonals, rows start   1,  1,   1,   1,    1,    1, ...   1,  3,   5,   7,    9,   11, ...   1,  5,  14,  28,   47,   71, ...   1,  7,  28,  76,  163,  301, ...   1,  9,  47, 163,  433,  961, ...   1, 11,  71, 301,  961, 2515, ...   1, 13, 100, 502, 1879, 5695, ... CROSSREFS Sequence in context: A302997 A144461 A106597 * A100936 A086620 A228356 Adjacent sequences:  A108356 A108357 A108358 * A108360 A108361 A108362 KEYWORD easy,nonn,tabl AUTHOR Paul Barry, May 31 2005 STATUS approved

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Last modified March 20 05:29 EDT 2019. Contains 321344 sequences. (Running on oeis4.)