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A112376 Sum of base and exponent of prime powers. 1

%I

%S 3,4,4,6,8,5,5,12,14,6,18,20,24,7,6,30,32,7,38,42,44,48,9,54,60,62,8,

%T 68,72,74,80,7,84,90,98,102,104,108,110,114,13,8,128,9,132,138,140,

%U 150,152,158,164,168,15,174,180,182,192,194,198,200,212,224,228,230,234,240,242

%N Sum of base and exponent of prime powers.

%C If n = p^q, where p is prime and q > 0, then p+q is in the sequence.

%C If n is not of that form, omit the term.

%C Might be a good "puzzle" sequence - guess the rule given the first ten or so terms.

%e n = 3 = 3^1, so 3+1 = 4 is a term; n = 4 = 2^2, so 2+2 = 4 is again a term; n = 5 = 5^1, so we get 5+1 =6.

%e But 6 is not a prime power, so we skip it.

%o (PARI) for(n=1,300,fac=factor(n);if(matsize(fac)[1]==1,print1(fac[1,1]+fac[1,2],",")))

%Y Cf. A112375, A064438.

%Y A008474 is another version, defined for all n.

%K nonn

%O 1,1

%A _Zak Seidov_, Dec 04 2005

%E Edited and extended by _Klaus Brockhaus_, Jan 21 2006

%E Further edited by _N. J. A. Sloane_, Nov 19 2018

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Last modified July 7 15:31 EDT 2020. Contains 335495 sequences. (Running on oeis4.)