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 A145668 a(n) = size of the n-th term in S(2) (defined in Comments). 2

%I

%S 2,2,1,1,5,3,4,9,2,1,1,7,4,1,1,4,1,1,1,1,1,1,1,12,1,20,1,1,1,1,1,1,1,

%T 1,1,5,29,19,1,1,1,1,1,1,1,4,1,1,2,1,1,1,3,1,75,2,19,4,1,7,1,1,1,1,1,

%U 1,1,1,1,1,2,1,4,1,1,1,2,1,2,1,1,1,1,23,1,82,76,1,1,3,1,1,3,3,4,2,3,3,1,2,1,1,3,1,1,1,3,1,3,1,9,1,2,1,1,1,3,2,2,1,1,1,1,1,1,1

%N a(n) = size of the n-th term in S(2) (defined in Comments).

%C Let H(L,b) be the Hamming graph whose vertices are the sequences of length L over the alphabet {0,1,...,b-1} with adjacency being defined by having Hamming distance 1. Let P(L,b) be the subgraph of H(L,b) induced by the set of vertices which are base b representations of primes with L digits (not allowing leading 0 digits). Let S(b) be the sequence of all components of the graphs P(L,b), L>0, sorted by the smallest prime in a component.

%Y Cf. A145667-A145674, A104080, A014234.

%K nonn,base

%O 1,1

%A _W. Edwin Clark_, Mar 17 2009

%E More terms from _Max Alekseyev_, May 12 2011

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Last modified June 17 13:58 EDT 2021. Contains 345080 sequences. (Running on oeis4.)