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.
%I A162299 #40 Feb 16 2025 08:33:10 %S A162299 1,2,2,6,2,3,1,4,2,4,30,1,3,2,5,1,12,1,12,2,6,42,1,6,1,2,2,7,1,12,1, %T A162299 24,1,12,2,8,30,1,9,1,15,1,3,2,9,1,20,1,2,1,10,1,4,2,10,66,1,2,1,1,1, %U A162299 1,1,6,2,11,1,12,1,8,1,6,1,8,1,12,2,12,2730,1,3,1,10,1,7,1,6,1,1,2,13,1,420,1,12,1,20,1,28,1,60,1,12,2,14,6,1,90,1,6,1,10,1,18,1,30,1,6,2,15 %N A162299 Faulhaber's triangle: triangle T(k,y) read by rows, giving denominator of the coefficient [m^y] of the polynomial Sum_{x=1..m} x^(k-1). %C A162299 There are many versions of Faulhaber's triangle: search the OEIS for his name. For example, A220862/A220963 is essentially the same as this triangle, except for an initial column of 0's. - _N. J. A. Sloane_, Jan 28 2017 %H A162299 Alois P. Heinz, <a href="/A162299/b162299.txt">Rows n = 0..140, flattened</a> %H A162299 Mohammad Torabi-Dashti, <a href="http://www.maa.org/programs/faculty-and-departments/classroom-capsules-and-notes/faulhaber-s-triangle">Faulhaber’s Triangle</a>, College Math. J., 42:2 (2011), 96-97. %H A162299 Mohammad Torabi-Dashti, <a href="/A162298/a162298.pdf">Faulhaber’s Triangle</a> [Annotated scanned copy of preprint] %H A162299 Eric Weisstein's MathWorld, <a href="https://mathworld.wolfram.com/PowerSum.html">Power Sum</a> %F A162299 Faulhaber's triangle of fractions H(n,k) (n >= 0, 1 <= k <= n+1) is defined by: H(0,1)=1; for 2<=k<=n+1, H(n,k) = (n/k)*H(n-1,k-1) with H(n,1) = 1 - Sum_{i=2..n+1}H(n,i). - _N. J. A. Sloane_, Jan 28 2017 %F A162299 Sum_{x=1..m} x^(k-1) = (Bernoulli(k,m+1)-Bernoulli(k))/k. %e A162299 The first few polynomials: %e A162299 m; %e A162299 m/2 + m^2/2; %e A162299 m/6 + m^2/2 + m^3/3; %e A162299 0 + m^2/4 + m^3/2 + m^4/4; %e A162299 -m/30 + 0 + m^3/3 + m^4/2 + m^5/5; %e A162299 ... %e A162299 Initial rows of Faulhaber's triangle of fractions H(n, k) (n >= 0, 1 <= k <= n+1): %e A162299 1; %e A162299 1/2, 1/2; %e A162299 1/6, 1/2, 1/3; %e A162299 0, 1/4, 1/2, 1/4; %e A162299 -1/30, 0, 1/3, 1/2, 1/5; %e A162299 0, -1/12, 0, 5/12, 1/2, 1/6; %e A162299 1/42, 0, -1/6, 0, 1/2, 1/2, 1/7; %e A162299 0, 1/12, 0, -7/24, 0, 7/12, 1/2, 1/8; %e A162299 -1/30, 0, 2/9, 0, -7/15, 0, 2/3, 1/2, 1/9; %e A162299 ... %e A162299 The triangle starts in row k=1 with columns 1<=y<=k as %e A162299 1 %e A162299 2 2 %e A162299 6 2 3 %e A162299 1 4 2 4 %e A162299 30 1 3 2 5 %e A162299 1 12 1 12 2 6 %e A162299 42 1 6 1 2 2 7 %e A162299 1 12 1 24 1 12 2 8 %e A162299 30 1 9 1 15 1 3 2 9 %e A162299 1 20 1 2 1 10 1 4 2 10 %e A162299 66 1 2 1 1 1 1 1 6 2 11 %e A162299 1 12 1 8 1 6 1 8 1 12 2 12 %e A162299 2730 1 3 1 10 1 7 1 6 1 1 2 13 %e A162299 1 420 1 12 1 20 1 28 1 60 1 12 2 14 %e A162299 6 1 90 1 6 1 10 1 18 1 30 1 6 2 15 %e A162299 ... %e A162299 Initial rows of triangle of fractions: %e A162299 1; %e A162299 1/2, 1/2; %e A162299 1/6, 1/2, 1/3; %e A162299 0, 1/4, 1/2, 1/4; %e A162299 -1/30, 0, 1/3, 1/2, 1/5; %e A162299 0, -1/12, 0, 5/12, 1/2, 1/6; %e A162299 1/42, 0, -1/6, 0, 1/2, 1/2, 1/7; %e A162299 0, 1/12, 0, -7/24, 0, 7/12, 1/2, 1/8; %e A162299 -1/30, 0, 2/9, 0, -7/15, 0, 2/3, 1/2, 1/9; %e A162299 ... %p A162299 A162299 := proc(k,y) local gf,x; gf := sum(x^(k-1),x=1..m) ; coeftayl(gf,m=0,y) ; denom(%) ; end proc: # _R. J. Mathar_, Jan 24 2011 %p A162299 # To produce Faulhaber's triangle of fractions H(n,k) (n >= 0, 1 <= k <= n+1): %p A162299 H:=proc(n,k) option remember; local i; %p A162299 if n<0 or k>n+1 then 0; %p A162299 elif n=0 then 1; %p A162299 elif k>1 then (n/k)*H(n-1,k-1); %p A162299 else 1 - add(H(n,i),i=2..n+1); fi; end; %p A162299 for n from 0 to 10 do lprint([seq(H(n,k),k=1..n+1)]); od: %p A162299 for n from 0 to 12 do lprint([seq(numer(H(n,k)),k=1..n+1)]); od: # A162298 %p A162299 for n from 0 to 12 do lprint([seq(denom(H(n,k)),k=1..n+1)]); od: # A162299 # _N. J. A. Sloane_, Jan 28 2017 %t A162299 H[n_, k_] := H[n, k] = Which[n < 0 || k > n+1, 0, n == 0, 1, k > 1, (n/k)* H[n - 1, k - 1], True, 1 - Sum[H[n, i], {i, 2, n + 1}]]; %t A162299 Table[H[n, k] // Denominator, {n, 0, 14}, {k, 1, n + 1}] // Flatten (* _Jean-François Alcover_, Aug 04 2022 *) %Y A162299 Cf. A000367, A162298 (numerators). %Y A162299 See also A220962/A220963. %Y A162299 Cf. A053382, A053383. %K A162299 nonn,tabl,frac %O A162299 0,2 %A A162299 _Juri-Stepan Gerasimov_, Jun 30 2009 and Jul 02 2009 %E A162299 Offset set to 0 by _Alois P. Heinz_, Feb 19 2021