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.

A335948 T(n, k) = denominator([x^k] b_n(x)), where b_n(x) = Sum_{k=0..n} binomial(n,k)* Bernoulli(k, 1/2)*x^(n-k). Triangle read by rows, for n >= 0 and 0 <= k <= n.

Original entry on oeis.org

1, 1, 1, 12, 1, 1, 1, 4, 1, 1, 240, 1, 2, 1, 1, 1, 48, 1, 6, 1, 1, 1344, 1, 16, 1, 4, 1, 1, 1, 192, 1, 48, 1, 4, 1, 1, 3840, 1, 48, 1, 24, 1, 3, 1, 1, 1, 1280, 1, 16, 1, 40, 1, 1, 1, 1, 33792, 1, 256, 1, 32, 1, 8, 1, 4, 1, 1, 1, 3072, 1, 256, 1, 32, 1, 8, 1, 12, 1, 1
Offset: 0

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Author

Peter Luschny, Jul 01 2020

Keywords

Comments

See A335947 for formulas and references concerning the polynomials.

Examples

			First few polynomials are:
b_0(x) = 1;
b_1(x) = x;
b_2(x) = -(1/12) + x^2;
b_3(x) = -(1/4)*x + x^3;
b_4(x) = (7/240) - (1/2)*x^2 + x^4;
b_5(x) = (7/48)*x - (5/6)*x^3 + x^5;
b_6(x) = -(31/1344) + (7/16)*x^2 - (5/4)*x^4 + x^6;
Triangle starts:
1;
1,     1;
12,    1,    1;
1,     4,    1,   1;
240,   1,    2,   1,  1;
1,     48,   1,   6,  1,  1;
1344,  1,    16,  1,  4,  1,  1;
1,     192,  1,   48, 1,  4,  1, 1;
3840,  1,    48,  1,  24, 1,  3, 1, 1;
1,     1280, 1,   16, 1,  40, 1, 1, 1, 1;
33792, 1,    256, 1,  32, 1,  8, 1, 4, 1, 1;
		

Crossrefs

Cf. A335947 (numerators), A157780 (column 0), A033469 (column 0 even indices only).