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A109446
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Binomial coefficients C(n,k) with n-k even, read by rows.
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1
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1, 1, 1, 1, 3, 1, 1, 6, 1, 5, 10, 1, 1, 15, 15, 1, 7, 35, 21, 1, 1, 28, 70, 28, 1, 9, 84, 126, 36, 1, 1, 45, 210, 210, 45, 1, 11, 165, 462, 330, 55, 1, 1, 66, 495, 924, 495, 66, 1, 13, 286, 1287, 1716, 715, 78, 1, 1, 91, 1001, 3003, 3003, 1001, 91, 1, 15, 455, 3003, 6435, 5005
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,5
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EXAMPLE
| Starred terms in Pascal's triangle (A007318), read by rows:
1*;
1, 1*;
1*, 2, 1*;
1, 3*, 3, 1*;
1*, 4, 6*, 4, 1*;
1, 5*, 10, 10*, 5, 1*;
1*, 6, 15*, 20, 15*, 6, 1*;
1, 7*, 21, 35*, 35, 21*, 7, 1*;
1*, 8, 28*, 56, 70*, 56, 28*, 8, 1*;
1, 9*, 36, 84*, 126, 126*, 84, 36*, 9, 1*;
Rows in A086645 (1; 1, 1; 1, 6, 1; ...) interspersed with rows in A103327 (1; 3, 1; 5, 10, 1; ...).
1; 1; 1, 1; 3, 1; 1, 6, 1; 5, 10, 1; 1, 15, 15, 1; 7, 35, 21, 1; ....
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MATHEMATICA
| Flatten[ Table[ If[ EvenQ[n - k], Binomial[n, k], {}], {n, 0, 15}, {k, 0, n}]] (* Robert G. Wilson v *)
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CROSSREFS
| Cf. A109447. See A054142 for another version.
Sequence in context: A115017 A088439 A162315 * A088441 A061857 A067433
Adjacent sequences: A109443 A109444 A109445 * A109447 A109448 A109449
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KEYWORD
| easy,nonn,tabf
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AUTHOR
| Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Aug 27 2005
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EXTENSIONS
| More terms from Robert G. Wilson v (rgwv(at)rgwv.com), Aug 30 2005
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