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

Author

Reinhard Zumkeller, Feb 11 2015

Keywords

• nonn

Links

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

Crossrefs

Cf. A254967, A000959.

Programs

Haskell

a254969 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 *)

Formula

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