cp's OEIS Frontend

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.

A350105 Number of subsets of the initial segment of the natural numbers strictly below n which are not self-measuring. Number of subsets S of [n] with S != distset(S).

Original entry on oeis.org

0, 0, 1, 3, 9, 22, 52, 112, 238, 490, 999, 2019, 4065, 8155, 16345, 32725, 65489, 131020, 262090, 524228, 1048514, 2097084, 4194232, 8388532, 16777138, 33554346, 67108775, 134217635, 268435359, 536870809, 1073741719, 2147483535, 4294967181, 8589934471, 17179869059
Offset: 0

Views

Author

Peter Luschny, Dec 16 2021

Keywords

Comments

We use the notation [n] = {0, 1, ..., n-1}. If S is a subset of [n] then we define the distset of S (set of distances of S) as {|x - y|: x, y in S}. We call a subset S of the natural numbers self-measuring if and only if S = distset(S).

Crossrefs

Programs

  • SageMath
    def A350105List(len):
        L = [0] * len
        b, z = 2, 2
        for n in (2..len-1):
            b += sloane.A000005(n - 1)
            z += z
            L[n] = z - b
        return L
    print(A350105List(35))

Formula

See the formulas in A350102.
a(n) = 2^n - A350102(n).