cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A080387 Numbers k such that there are exactly 10 numbers j for which binomial(k, floor(k/2)) / binomial(k,j) is an integer, i.e., A080383(k) = 10.

Original entry on oeis.org

13, 31, 41, 57, 85, 91, 133, 155, 177, 183, 209, 221, 253, 281, 307, 313, 341, 375, 381, 409, 419, 441, 457, 463, 477, 481, 533, 553, 599, 617, 625, 631, 645, 651, 661, 691, 737, 757, 829, 841, 859, 871, 881, 885, 901, 919, 929, 937, 953, 967, 987, 993
Offset: 1

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Author

Labos Elemer, Mar 12 2003

Keywords

Examples

			For n=13, the central binomial coefficient (C(13,6) = 1716) is divisible by 10 binomial coefficients C(13,j); the 4 nondivisible cases are C(13,4), C(13,5), C(13,8), and C(13,9).
		

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