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.

A058898 Inconsummate numbers in base 2: no number is this multiple of the sum of its digits (in base 2).

Original entry on oeis.org

13, 19, 25, 26, 35, 38, 47, 49, 50, 52, 55, 67, 70, 76, 94, 95, 97, 98, 100, 103, 104, 109, 110, 115, 117, 131, 134, 140, 151, 152, 157, 159, 171, 175, 179, 183, 185, 187, 188, 190, 193, 194, 196, 199, 200, 203, 206, 208, 217, 218, 220, 227, 229
Offset: 1

Views

Author

N. J. A. Sloane, Jan 09 2001

Keywords

Comments

Equivalently, these are the natural numbers that cannot be written as the arithmetic mean of distinct powers of 2. - Brian Kell, Feb 28 2009

Crossrefs

Programs

  • Maple
    For Maple code see A058906.
  • Mathematica
    Do[k = n; While[ Apply[ Plus, IntegerDigits[k, 2] ]*n != k && k < 250n, k += n]; If[k == 250n, Print[n] ], {n, 1, 10^3} ]
  • Python
    from itertools import count, islice, combinations_with_replacement
    def A058898_gen(startvalue=1): # generator of terms >= startvalue
        for n in count(max(startvalue,1)):
            for l in count(1):
                if l*n < 1<0 and sorted(bin(s*n)[2:]) == [str(e) for e in d]:
                        break
                else:
                    continue
                break
    A058898_list = list(islice(A058898_gen(),20)) # Chai Wah Wu, May 09 2023

Formula

n such that A065413(n) = 0. - Brian Kell, Mar 01 2009