A385482 a(n) is the least number k such that k*n is a binary Niven number (A049445).
1, 1, 2, 1, 2, 1, 3, 1, 2, 1, 5, 1, 10, 3, 4, 1, 2, 1, 12, 1, 1, 3, 3, 1, 12, 5, 3, 3, 4, 2, 5, 1, 2, 1, 12, 1, 5, 6, 4, 1, 5, 1, 4, 3, 4, 2, 12, 1, 12, 6, 4, 3, 4, 2, 1, 3, 4, 2, 5, 1, 6, 5, 2, 1, 2, 1, 12, 1, 1, 6, 4, 1, 6, 3, 4, 3, 4, 2, 5, 1, 1, 3, 4, 1, 4
Offset: 1
Links
- Amiram Eldar, Table of n, a(n) for n = 1..10000
Crossrefs
Programs
-
Mathematica
a[n_] := Module[{m = n, k = 1}, While[!Divisible[m, DigitSum[m, 2]], m += n; k++]; k]; Array[a, 100] -
PARI
a(n) = {my(m = n, k = 1); while(m % hammingweight(m), m += n; k++); k;} -
Python
from itertools import count def a(n): return next(k for k in count(1) if (m:=k*n)%m.bit_count() == 0) print([a(n) for n in range(1, 86)]) # Michael S. Branicky, Jun 30 2025