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Number of holes in decimal expansion of n-th prime.
2

%I #16 Sep 27 2019 12:56:34

%S 0,0,0,0,0,0,0,1,0,1,0,0,1,1,1,0,1,1,1,0,0,1,2,3,1,1,1,1,2,0,0,0,0,1,

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

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

%N Number of holes in decimal expansion of n-th prime.

%C This is A064692 restricted to the primes.

%H Rémy Sigrist, <a href="/A327462/b327462.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) forprime (p=2, 439, print1 (vecsum(apply(d -> [1, 0, 0, 0, 1, 0, 1, 0, 2, 1][1+d], digits(p))) ", ")) \\ _Rémy Sigrist_, Sep 27 2019

%Y Cf. A035103, A064692, A249572, A250256, A327820.

%K nonn,base

%O 1,23

%A _N. J. A. Sloane_, Sep 27 2019