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A151993
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Number of Honaker primes (A033548) less than 10^n.
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0
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0, 0, 3, 63, 410, 2949, 21622, 175504, 1478015, 12330087, 107585476, 937135794
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,3
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COMMENTS
| G. L. Honaker, Jr. computed the first six terms. Are there an infinite number of Honaker primes?
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EXAMPLE
| a(3) = 3 because 131, 263, and 457 are the only Honaker primes less than 10^3.
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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]]
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CROSSREFS
| Cf. A006880 (primes < 10^n).
Sequence in context: A123754 A048354 A046181 * A120053 A139293 A133275
Adjacent sequences: A151990 A151991 A151992 * A151994 A151995 A151996
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KEYWORD
| hard,nonn,base
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AUTHOR
| T. D. Noe (noe(AT)sspectra.com), Sep 14 2009
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