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A075177 Indices of additive primes - primes with prime sum-of-digits, see A046704. +0
2
1, 2, 3, 4, 5, 9, 10, 13, 14, 15, 18, 19, 23, 24, 26, 30, 32, 33, 34, 36, 37, 40, 41, 43, 44, 45, 46, 48, 49, 50, 53, 56, 57, 60, 61, 64, 65, 66, 67, 68, 71, 72, 74, 75, 78, 79, 80, 82, 86, 87, 89, 90, 91, 93, 102, 105, 106, 108, 109, 110, 111, 116, 117, 118, 121, 124, 128 (list; graph; listen)
OFFSET

1,2

COMMENT

There are 107 additive primes among first 200 primes. There are 38455 additive primes among first 100000 primes. Additive primes are in A046704.

LINKS

Zak Seidov, Table of n, a(n) for n=1..4086, a(n)<10^4.

FORMULA

PrimePi[A046704(n)]

EXAMPLE

Prime(10)=29 is additive prime because 2+9=11 is prime.

MATHEMATICA

Map[PrimePi[ # ]&, Select[Prime[Range[200]], PrimeQ[Apply[ Plus, IntegerDigits[ # ]]]&]

CROSSREFS

Cf. A046704.

Sequence in context: A139456 A081869 A015837 this_sequence A062096 A143827 A100797

Adjacent sequences: A075174 A075175 A075176 this_sequence A075178 A075179 A075180

KEYWORD

nonn,base

AUTHOR

Zak Seidov (zakseidov(AT)yahoo.com), Sep 06 2002

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Last modified November 25 20:09 EST 2009. Contains 167514 sequences.


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