A151993 Number of Honaker primes (A033548) less than 10^n.

0, 0, 3, 63, 410, 2949, 21622, 175504, 1478015, 12330087, 107585476, 937135794

Offset: 1

Author

T. D. Noe, Sep 14 2009

Keywords

• hard
• nonn
• base

Comments

G. L. Honaker, Jr. computed the first six terms. Are there an infinite number of Honaker primes?

Examples

			a(3) = 3 because 131, 263, and 457 are the only Honaker primes less than 10^3.
		

Crossrefs

Cf. A006880 (primes < 10^n).

Programs

Mathematica

nn=6; cnt=0; power10=10; Reap[Do[p=Prime[k]; If[p>power10, Sow[cnt]; power10=10*power10]; If[Total[IntegerDigits[k]] == Total[IntegerDigits[p]], cnt++ ], {k,PrimePi[10^nn]+1}]][[2,1]]