A363634 - OEIS

A363634

Lucky numbers that are products of smaller lucky numbers.

1, 9, 21, 49, 63, 75, 93, 99, 105, 111, 129, 135, 169, 189, 195, 201, 219, 231, 237, 259, 261, 273, 297, 357, 399, 429, 477, 483, 489, 495, 511, 553, 559, 579, 615, 621, 645, 651, 693, 723, 729, 735, 777, 801, 805, 819, 855, 867, 897, 903, 925, 931, 957, 961

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

1 is a term because it is a lucky number and equals the empty product.

21 is a term because 21 = 3*7 and both 21 and the two factors 3 and 7 are lucky numbers.

729 is a term because 729 = 9*9*9 and both 729 and 9 are lucky numbers. (This is the first term that requires more than two factors.)

CROSSREFS

Cf. A000959, A363635, A363636.

Sequence in context: A133762 A160414 A256530 * A118130 A144482 A251212

Adjacent sequences: A363631 A363632 A363633 * A363635 A363636 A363637

KEYWORD

nonn

AUTHOR

Pontus von Brömssen, Jun 19 2023

STATUS

approved