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%I #7 Nov 19 2018 20:46:33
%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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