login

Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.

A377801
Irregular triangle read by rows: row n lists divisors of n-th Bell number.
1
1, 1, 1, 2, 1, 5, 1, 3, 5, 15, 1, 2, 4, 13, 26, 52, 1, 7, 29, 203, 1, 877, 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18, 20, 23, 30, 36, 45, 46, 60, 69, 90, 92, 115, 138, 180, 207, 230, 276, 345, 414, 460, 690, 828, 1035, 1380, 2070, 4140, 1, 3, 7, 19, 21, 53, 57, 133, 159, 371, 399, 1007, 1113, 3021, 7049, 21147
OFFSET
0,4
LINKS
Amiram Eldar, Table of n, a(n) for n = 0..7035 (rows 0..103 flattened)
FORMULA
T(n,k) = A027750(A000110(n),k).
T(n,2) = A279623(n) for n>=2.
EXAMPLE
Triangle begins:
1,
1,
1, 2,
1, 5,
1, 3, 5, 15,
1, 2, 4, 13, 26, 52,
1, 7, 29, 203,
1, 877,
...
MATHEMATICA
Flatten[Table[Divisors[BellB[n]], {n, 0, 20}]]
PROG
(Magma) /* As triangle */ [Divisors(Bell(n)): n in [0..30]];
CROSSREFS
Row sums give A262349.
Row lengths give A278973.
Sequence in context: A055205 A342001 A347957 * A369038 A161686 A289621
KEYWORD
nonn,tabf
AUTHOR
Vincenzo Librandi, Nov 07 2024
STATUS
approved