A118695 Semiprimes which are divisible by their digital root.

4, 6, 9, 10, 21, 38, 39, 46, 55, 57, 74, 82, 91, 93, 95, 111, 118, 129, 133, 145, 146, 183, 185, 201, 217, 218, 219, 226, 235, 237, 253, 254, 259, 262, 289, 291, 298, 309, 326, 327, 334, 361, 362, 365, 381, 398, 415, 417, 451, 453, 469, 471, 478, 489, 505, 511, 514, 542, 543

Offset: 1

Author

Luc Stevens (lms022(AT)yahoo.com), May 20 2006

Keywords

• base
• nonn

Examples

			95 is a semiprime and it is divisible by its digital root 5.
		

Links

• Amiram Eldar, Table of n, a(n) for n = 1..10000

Crossrefs

Intersection of A001358 and A064807.

Cf. A010888.

Programs

Mathematica

Select[Range[550], PrimeOmega[#] == 2 && Divisible[#, Mod[# - 1, 9] + 1] &] (* Amiram Eldar, Feb 06 2021 *)

Extensions

Data corrected by Amiram Eldar, Feb 06 2021