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A328932 Number of primes that are a concatenation of two positive integers whose sum is prime(n).

%I A328932 #12 Nov 04 2019 14:33:47
%S A328932 1,0,2,2,4,3,2,6,5,9,6,7,10,11,12,14,12,16,14,17,12,15,16,20,19,19,20,
%T A328932 17,23,23,18,27,28,24,30,25,26,26,28,30,27,30,32,27,25,27,37,42,38,32,
%U A328932 32,33,30,39,38,36,43,38,43,42,36,36,47,47,49,38,45,48,51,50
%N A328932 Number of primes that are a concatenation of two positive integers whose sum is prime(n).
%H A328932 Alois P. Heinz, <a href="/A328932/b328932.txt">Table of n, a(n) for n = 1..10000</a>
%F A328932 a(n) = A328903(A000040(n)).
%e A328932 a(3) = 2 because primes 23, 41 are concatenations of prime(3) = 5 = 2 + 3 = 4 + 1.
%p A328932 a:= n-> (p-> add(`if`(isprime(parse(cat(i,
%p A328932         p-i))), 1, 0), i=1..p-1))(ithprime(n)):
%p A328932 seq(a(n), n=1..80);  # _Alois P. Heinz_, Oct 31 2019
%Y A328932 Subsequence of A328903.
%Y A328932 Cf. A000040, A066686, A067754.
%K A328932 nonn,base,easy
%O A328932 1,3
%A A328932 _Juri-Stepan Gerasimov_, Oct 31 2019