OFFSET
1,3
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..4788 (rows for n = 1..1024)
FORMULA
T(n, 1) = 1.
T(n, A343650(n)) = n.
EXAMPLE
Triangle T(n, k) begins:
1: [1]
2: [1, 2]
3: [1, 3]
4: [1, 2, 4]
5: [1, 5]
6: [1, 2, 3, 6]
7: [1, 7]
8: [1, 2, 4, 8]
9: [1, 9]
10: [1, 2, 5, 10]
11: [1, 11]
12: [1, 2, 3, 4, 6, 12]
13: [1, 13]
14: [1, 2, 7, 14]
15: [1, 3, 5, 15]
PROG
(PARI) row(n, h=hammingweight) = my (hn=h(n)); select(d -> hn==h(d)*h(n/d), divisors(n))
CROSSREFS
KEYWORD
nonn,tabf,base
AUTHOR
Rémy Sigrist, Apr 25 2021
STATUS
approved