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 A197420 Triangle with the denominator of the coefficient [x^k] of the second order Bernoulli polynomial B_n^(2)(x) in row n, column 0<=k<=n. 2
 1, 1, 1, 6, 1, 1, 2, 2, 1, 1, 10, 1, 1, 1, 1, 6, 2, 1, 3, 1, 1, 42, 1, 2, 1, 2, 1, 1, 6, 6, 2, 2, 2, 2, 1, 1, 30, 3, 3, 3, 1, 1, 3, 1, 1, 10, 10, 1, 1, 1, 5, 1, 1, 1, 1, 22, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 6, 2, 2, 2, 1, 1, 1, 1, 2, 6, 1, 1, 2730, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS Denominators of the polynomials defined in A197419. LINKS R. Dere, Y. Simsek, Bernoulli type polynomials on Umbral Algebra, arXiv:1110.1484 [math.CA] EXAMPLE 1; 1,1; 6,1,1; 2,2,1,1; 10,1,1,1,1; 6,2,1,3,1,1; 42,1,2,1,2,1,1; 6,6,2,2,2,2,1,1; 30,3,3,3,1,1,3,1,1; 10,10,1,1,1,5,1,1,1,1; 22,1,2,1,1,1,1,1,2,1,1; 6,2,2,2,1,1,1,1,2,6,1,1; 2730,1,1,1,2,1,1,1,2,1,1,1,1; MATHEMATICA t[n_, m_] := If [n == m, 1, 2*Binomial[n, m]*Sum[StirlingS2[n-m, k]*StirlingS1[2+k, 2]/((k+1)*(2+k)), {k, 1, n-m}]]; Table[t[n, m] // Denominator, {n, 0, 12}, {m, 0, n}] // Flatten (* Jean-François Alcover, Dec 12 2013, after Vladimir Kruchinin *) CROSSREFS Sequence in context: A316623 A108131 A073354 * A128423 A133419 A010134 Adjacent sequences:  A197417 A197418 A197419 * A197421 A197422 A197423 KEYWORD nonn,tabl,frac AUTHOR R. J. Mathar, Oct 14 2011 STATUS approved

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Last modified December 6 06:34 EST 2019. Contains 329784 sequences. (Running on oeis4.)