A328937 The number of imprimitive 3-Carmichael numbers (A087788 and A328935) below 10^n.

4, 11, 25, 59, 127, 252, 471, 928, 1734, 3462, 6615, 12725, 24396, 46877, 89854, 173331, 334737, 647265, 1253176

Offset: 6

Author

Amiram Eldar, Oct 31 2019

Keywords

• nonn
• more

Comments

Granville and Pomerance conjectured that most Carmichael numbers are imprimitive, i.e. lim_{n->oo} a(n)/A132195(n) = 1.

Examples

			a(6) = 4 since there are 4 imprimitive 3-Carmichael numbers below 10^6: 294409, 399001, 488881, 512461.
		

Links

• J. M. Chick, Carmichael number variable relations: three-prime Carmichael numbers up to 10^24, arXiv preprint arXiv:0711.2915 [math.NT] (2007).
• Andrew Granville and Carl Pomerance, Two contradictory conjectures concerning Carmichael numbers, Mathematics of Computation, Vol. 71, No. 238 (2002), pp. 883-908.

Crossrefs

Cf. A002997, A087788, A132195, A328935.