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A109066 Number of prime digits in n-th prime. 10

%I

%S 1,1,1,1,0,1,1,0,2,1,1,2,0,1,1,2,1,0,1,1,2,1,1,0,1,0,1,1,0,1,2,1,2,1,

%T 0,1,2,1,1,2,1,0,0,1,1,0,1,3,3,2,3,2,1,2,3,2,1,2,3,1,2,2,2,1,2,2,2,3,

%U 2,1,3,2,2,3,2,2,1,2,0,0,0,1,1,2,1,1,0,2,0,1,1,1,1,0,0,2,1,2,3,1,2,3,2,1,2

%N Number of prime digits in n-th prime.

%C The prime A000040(n) is in A034844 iff a(n) = 0; it is in A179336 iff a(n) > 0. [_Reinhard Zumkeller_, Jul 11 2010, corrected by _M. F. Hasler_, Aug 27 2012]

%H Reinhard Zumkeller, <a href="/A109066/b109066.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A193238(A000040(n)). [_Reinhard Zumkeller_, Jul 19 2011]

%t a[n_]:=Count[PrimeQ/@IntegerDigits[Prime[n]], True]

%o (PARI) a(n) = vecsum(apply(x->isprime(x), digits(prime(n)))); \\ _Michel Marcus_, Mar 15 2019

%Y Cf. A019546 (primes whose digits are primes), A092629 (number of prime digits is nonprime), A104250 (sum of prime digits of n-th prime).

%Y Cf. A000040, A034844, A179336.

%K base,nonn

%O 1,9

%A _Zak Seidov_, Jun 17 2005

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Last modified August 11 00:32 EDT 2020. Contains 336403 sequences. (Running on oeis4.)