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 A341724 #26 Sep 08 2023 13:06:13 %S A341724 1,-2,1,8,-4,1,-50,24,-6,1,416,-200,48,-8,1,-4322,2080,-500,80,-10,1, %T A341724 53888,-25932,6240,-1000,120,-12,1,-783890,377216,-90762,14560,-1750, %U A341724 168,-14,1,13031936,-6271120,1508864,-242032,29120,-2800,224,-16,1 %N A341724 Triangle read by rows: coefficients of expansion of certain sums P_2(n,k) of Fibonacci numbers as a sum of powers. %C A341724 Conjectures from _Mélika Tebni_, Sep 04 2023: (Start) %C A341724 For 0 < k < p and p prime, T(p,k) == 0 (mod p). %C A341724 For 0 <= k < n and n = 2^m (m natural number), T(n,k) == 0 (mod n). (End) %D A341724 Anthony G. Shannon and Richard L. Ollerton. "A note on Ledin’s summation problem." The Fibonacci Quarterly 59:1 (2021), 47-56. See Table 3. %F A341724 From _Mélika Tebni_, Sep 04 2023: (Start) %F A341724 E.g.f. of column k: x^k / ((1-2*sinh(-x))*k!). %F A341724 T(n,k) = (-1)^(n-k)*binomial(n,k)*A000557(n-k). %F A341724 Recurrence: T(n,0) = (-1)^n*A000557(n) and T(n,k) = n*T(n-1,k-1) / k, n >= k >= 1. (End) %F A341724 From _Alois P. Heinz_, Sep 04 2023: (Start) %F A341724 |Sum_{k=0..n} T(n,k)| = A000556(n). %F A341724 Sum_{k=0..n} |T(n,k)| = A005923(n). %F A341724 Sum_{k=0..n} k * T(n,k) = A341726(n). (End) %e A341724 Triangle begins: %e A341724 1; %e A341724 -2, 1; %e A341724 8, -4, 1; %e A341724 -50, 24, -6, 1; %e A341724 416, -200, 48, -8, 1; %e A341724 -4322, 2080, -500, 80, -10, 1; %e A341724 53888, -25932, 6240, -1000, 120, -12, 1; %e A341724 -783890, 377216, -90762, 14560, -1750, 168, -14, 1; %e A341724 13031936, -6271120, 1508864, -242032, 29120, -2800, 224, -16, 1; %e A341724 ... %p A341724 egf:= k-> x^k / ((1-2*sinh(-x))*k!): %p A341724 A341724:= (n,k)-> n! * coeff(series(egf(k), x, n+1), x, n): %p A341724 seq(print(seq(A341724(n,k), k=0..n)), n=0..8); # _Mélika Tebni_, Sep 04 2023 %Y A341724 Column 0 is a signed version of A000557, column 1 is A341727. %Y A341724 Cf. A000556, A005923, A341723, A341725, A341726. %K A341724 sign,tabl %O A341724 0,2 %A A341724 _N. J. A. Sloane_, Mar 04 2021