A382896 Smith sphenic numbers, i.e., Smith numbers (A006753) that are the product of three distinct prime numbers.

438, 483, 627, 645, 654, 663, 762, 861, 915, 1086, 1581, 1626, 1842, 2067, 2265, 2373, 2409, 2679, 2751, 3138, 3246, 3345, 3615, 4173, 4191, 4209, 4974, 5253, 5298, 5397, 5946, 6054, 6315, 6531, 6567, 6585, 6603, 6693, 6702, 6855, 6981, 7026, 7089, 7287

Offset

1,1

Links

Shyam Sunder Gupta, Table of n, a(n) for n = 1..7523

Shyam Sunder Gupta, Smith Numbers, Exploring the Beauty of Fascinating Numbers, Springer (2025) Ch. 4, 127-157.

Example

438 is a term since 438 = 2 * 3 * 73, so it is the product of three distinct prime numbers (2, 3, and 73) and also a Smith number (4 + 3 + 8 = 2 + 3 + 7 + 3).

Crossrefs

Intersection of A006753 and A007304.

Sequence in context: A084293 A237939 A088893 * A043447 A006911 A222877

Adjacent sequences: A382893 A382894 A382895 * A382897 A382898 A382899

Keyword

nonn,base

Author

Shyam Sunder Gupta, Apr 08 2025

Status

approved