OFFSET
1,3
COMMENTS
LINKS
EXAMPLE
The first terms, alongside their binary representation and corresponding set S, are:
n a(n) bin(a(n)) S
-- ---- ---------- ------------------
1 0 0 {}
2 1 1 {1}
3 2 10 {2}
4 4 100 {3}
5 7 111 {1, 2, 3}
6 8 1000 {4}
7 16 10000 {5}
8 32 100000 {6}
9 39 100111 {1, 2, 3, 6}
10 42 101010 {2, 4, 6}
11 64 1000000 {7}
12 128 10000000 {8}
13 175 10101111 {1, 2, 3, 4, 6, 8}
14 256 100000000 {9}
15 291 100100011 {1, 2, 6, 9}
16 292 100100100 {3, 6, 9}
PROG
(PARI) is(n) = { my (b=Vecrev(binary(n)), s=select(k -> b[k], [1..#b])); vecsum(s) % lcm(s)==0 }
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Rémy Sigrist, Sep 26 2020
STATUS
approved