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A106492
Total sum of bases and exponents in Quetian Superfactorization of n, excluding the unity-exponents at the tips of branches.
4
0, 2, 3, 4, 5, 5, 7, 5, 5, 7, 11, 7, 13, 9, 8, 6, 17, 7, 19, 9, 10, 13, 23, 8, 7, 15, 6, 11, 29, 10, 31, 7, 14, 19, 12, 9, 37, 21, 16, 10, 41, 12, 43, 15, 10, 25, 47, 9, 9, 9, 20, 17, 53, 8, 16, 12, 22, 31, 59, 12, 61, 33, 12, 7, 18, 16, 67, 21, 26, 14, 71, 10, 73, 39, 10, 23, 18
OFFSET
1,2
FORMULA
Additive with a(p^e) = p + a(e).
EXAMPLE
a(64) = 7, as 64 = 2^6 = 2^(2^1*3^1) and 2+2+3=7. Similarly, for 360 = 2^(3^1) * 3^(2^1) * 5^1 we get a(360) = 2+3+3+2+5 = 15. See comments at A106490.
MAPLE
a:= proc(n) option remember;
add(i[1]+a(i[2]), i=ifactors(n)[2])
end:
seq(a(n), n=1..100); # Alois P. Heinz, Nov 06 2014
MATHEMATICA
a[1] = 0; a[n_] := a[n] = #[[1]] + a[#[[2]]]& /@ FactorInteger[n] // Total; Array[a, 100] (* Jean-François Alcover, Mar 03 2016 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 09 2005 based on Leroy Quet's message ('Super-Factoring' An Integer) posted to SeqFan-mailing list on Dec 06 2003.
STATUS
approved