cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A112376 Sum of base and exponent of prime powers.

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%I A112376 #15 Jun 09 2024 08:50:51
%S A112376 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 A112376 68,72,74,80,7,84,90,98,102,104,108,110,114,13,8,128,9,132,138,140,
%U A112376 150,152,158,164,168,15,174,180,182,192,194,198,200,212,224,228,230,234,240,242
%N A112376 Sum of base and exponent of prime powers.
%C A112376 If n = p^q, where p is prime and q > 0, then p+q is in the sequence.
%C A112376 If n is not of that form, omit the term.
%C A112376 Might be a good "puzzle" sequence - guess the rule given the first ten or so terms.
%H A112376 Michael De Vlieger, <a href="/A112376/b112376.txt">Table of n, a(n) for n = 1..10000</a>
%e A112376 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 A112376 But 6 is not a prime power, so we skip it.
%t A112376 fsum[a_] := Total[Flatten[FactorInteger[a]]]; fsum/@Select[Range[242], PrimePowerQ](* _James C. McMahon_, Jun 08 2024 *)
%o A112376 (PARI) for(n=1,300,fac=factor(n);if(matsize(fac)[1]==1,print1(fac[1,1]+fac[1,2],",")))
%Y A112376 Cf. A112375, A064438.
%Y A112376 A008474 is another version, defined for all n.
%K A112376 nonn
%O A112376 1,1
%A A112376 _Zak Seidov_, Dec 04 2005
%E A112376 Edited and extended by _Klaus Brockhaus_, Jan 21 2006
%E A112376 Further edited by _N. J. A. Sloane_, Nov 19 2018