A192490 - OEIS

A192490

Characteristic function of ludic numbers (A003309).

1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0

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OFFSET

COMMENTS

a(A003309(n)) = 1 and a(A192607(n)) = 0.

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Index entries for characteristic functions

MATHEMATICA

a3309[nmax_] := a3309[nmax] = Module[{t = Range[2, nmax], k, r = {1}},

While[Length[t] > 0, k = First[t]; AppendTo[r, k];

t = Drop[t, {1, -1, k}]]; r];

ludicQ[n_, nmax_] /; 1 <= n <= nmax := MemberQ[a3309[nmax], n];