A373303 First differences of A371176.

1, 2, 2, 2, 2, 2, 4, 2, 2, 4, 4, 4, 2, 2, 4, 4, 4, 4, 4, 8, 2, 2, 4, 4, 4, 4, 4, 8, 4, 4, 8, 8, 8, 2, 2, 4, 4, 4, 4, 4, 8, 4, 4, 8, 8, 8, 4, 4, 8, 8, 8, 8, 8, 16, 2, 2, 4, 4, 4, 4, 4, 8, 4, 4, 8, 8, 8, 4, 4, 8, 8, 8, 8, 8, 16, 4, 4, 8, 8, 8, 8, 8, 16, 8, 8, 16, 16

Offset: 1

Author

Michel Marcus, May 31 2024

Keywords

• nonn

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000
• Alistair Bird, Jozef Schreier, Schreier sets and the Fibonacci sequence, Out Of The Norm blog, May 13 2012.

Crossrefs

Cf. A371176.

Programs

Mathematica

Differences[Join[{1}, Select[Range[2, 1000, 2], DigitSum[#, 2] <= IntegerExponent[#, 2] + 1 &]]] (* Paolo Xausa, Aug 12 2025 *)

PARI

isok(n) = hammingweight(n) <= (valuation(n, 2) + 1);
my(v=select(isok, [1..500])); vector(#v-1, k, v[k+1]-v[k])

Formula

a(n) = A371176(n+1) - A371176(n).