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A308730
Smallest prime p for which n is the least number of 1's in the base-2 representation of a multiple of p.
0
2, 3, 7, 89, 31, 13367, 127, 2099863, 178481
OFFSET
1,1
COMMENTS
It is not known if a(n) actually exists for all n. If there are infinitely many Mersenne primes, then a(n) is defined for infinitely many n.
The corresponding multipliers for n = 1,2,...,7 are 1,1,1,1,1,5,1,1,1. (Computations done by Leon Witzman.)
FORMULA
A086342(a(n)) = n. - Rémy Sigrist, Jul 06 2019
CROSSREFS
Sequence in context: A288800 A247025 A053964 * A062578 A062529 A308917
KEYWORD
nonn,base,more
AUTHOR
Jeffrey Shallit, Jun 20 2019
STATUS
approved