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a(n) is the number of primes q less than n-th prime p for which the Euclidean algorithm for p,q has exactly 2 nonzero remainders.
2

%I #14 Aug 08 2021 08:38:13

%S 0,0,1,1,1,2,4,3,2,3,2,4,6,5,3,2,5,3,5,5,5,6,3,6,6,7,5,5,6,5,7,4,7,5,

%T 8,4,8,6,5,4,4,7,6,6,8,7,7,9,10,7,6,4,9,7,8,9,7,7,6,8,4,4,10,6,7,9,7,

%U 7,8,5,11,4,9,10,10,6,9,7,12,12,9,9,7,12

%N a(n) is the number of primes q less than n-th prime p for which the Euclidean algorithm for p,q has exactly 2 nonzero remainders.

%e For prime(6)=13, the primes counted are 7 and 11.

%Y Cf. A049849, A049850.

%K nonn

%O 1,6

%A _Clark Kimberling_

%E More terms from _Sean A. Irvine_, Aug 07 2021