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 A084440 Number of ways to write the n-th prime as 1+p+p^k, p prime and k>0. 5

%I

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

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

%U 1,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,0,0,1,0,0,0,0,0,0,1,0,0

%N Number of ways to write the n-th prime as 1+p+p^k, p prime and k>0.

%C a(A084441(n))>0, a(A084442(n))=1, a(A084443(n))=0.

%e a(11)=2: prime(11) = 31 = 1+5+5^2 = 1+3+3^3.

%K nonn

%O 1,4

%A _Reinhard Zumkeller_, May 26 2003

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Last modified September 26 13:34 EDT 2021. Contains 347668 sequences. (Running on oeis4.)