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 A333140 a(n) is the least multiple of n of the form Sum_{k >= 0} e_k * b^k where b > 2 and Sum_{k >= 0} e_k * 2^k is the binary representation of n. 1

%I

%S 1,4,6,16,10,12,21,64,126,30,2211,36,3601,84,585,256,4097,630,194503,

%T 4160,273,234762,391276,1512,551125,474578,756,336,954274,120,341,

%U 1024,32769,32776,33554465,252,90225721,79236650,79236651,33280,147087951,1092

%N a(n) is the least multiple of n of the form Sum_{k >= 0} e_k * b^k where b > 2 and Sum_{k >= 0} e_k * 2^k is the binary representation of n.

%C To compute a(n): interpret the binary representation of n in base A155078(n).

%H Rémy Sigrist, <a href="/A333140/b333140.txt">Table of n, a(n) for n = 1..10000</a>

%e For n = 42:

%e - the binary representation of 42 is "101010",

%e - A155078(42) = 4,

%e - so a(42) = 4^5 + 4^3 + 4^1 = 1092.

%o (PARI) a(n) = { my (d=binary(n)); for (b=3, oo, my (r=fromdigits(d,b)); if (r%n==0, return (r))) }

%Y Cf. A155078.

%K nonn,base

%O 1,2

%A _Rémy Sigrist_, Mar 09 2020

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Last modified November 26 21:15 EST 2022. Contains 358362 sequences. (Running on oeis4.)