A254969 Central terms of the triangle of iterated absolute differences of lucky numbers.

1, 4, 2, 2, 2, 2, 2, 0, 2, 2, 0, 0, 0, 0, 0, 2, 2, 0, 0, 2, 0, 0, 0, 2, 2, 0, 2, 2, 2, 2, 0, 2, 2, 0, 0, 0, 0, 2, 0, 2, 0, 0, 2, 0, 2, 0, 2, 2, 0, 2, 2, 2, 2, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 2, 2, 0, 0, 2, 0, 2, 2, 2, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0

Offset

0,2

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

Formula

a(n) = A254967(2*n,n).

Mathematica

nmax = 85; (* index of last term *)
imax = 600; (* last index of initial lucky array L *)
L = Table[2 i + 1, {i, 0, imax}];
For[n = 2, n < Length[L], r = L[[n++]]; L = ReplacePart[L, Table[r*i -> Nothing, {i, 1, Length[L]/r}]]];
T[n_, n_] := If[n + 1 <= Length[L], L[[n + 1]], Print["imax should be increased"]; 0];
T[n_, k_] := T[n, k] = Abs[T[n, k + 1] - T[n - 1, k]];
a[n_] := T[2n, n];
Table[a[n], {n, 0, nmax}] (* Jean-François Alcover, Sep 22 2021 *)

Prog

(Haskell)
a254969 n = a254967 (2 * n) n

Crossrefs

Cf. A254967, A000959.

Sequence in context: A350788 A282698 A136709 * A137239 A136714 A280135

Adjacent sequences: A254966 A254967 A254968 * A254970 A254971 A254972

Keyword

nonn

Author

Reinhard Zumkeller, Feb 11 2015

Status

approved