OFFSET
1,3
COMMENTS
G. L. Honaker, Jr. computed the first six terms. Are there an infinite number of Honaker primes?
EXAMPLE
a(3) = 3 because 131, 263, and 457 are the only Honaker primes less than 10^3.
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]]
CROSSREFS
KEYWORD
hard,nonn,base
AUTHOR
T. D. Noe, Sep 14 2009
STATUS
approved