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A085702
Numbers k such that the sum of primes dividing k (with repetition) / smallest prime dividing k = largest prime dividing k.
1
4, 27, 30, 70, 84, 286, 308, 440, 528, 594, 646, 728, 884, 945, 1040, 1170, 1248, 1404, 1496, 1748, 1798, 1976, 3125, 3128, 3344, 3526, 3570, 3762, 3808, 4250, 4284, 5100, 5336, 5440, 5445, 5586, 6068, 6120, 6528, 6650, 7198, 7344, 7980, 8084, 8085, 8262
OFFSET
1,1
LINKS
EXAMPLE
308 is a term: 308 = 2^2*7*11, 2+2+7+11 = 22, and 22/2 = 11.
MATHEMATICA
q[k_] := Module[{f = FactorInteger[k]}, f[[1, 1]] * f[[-1, 1]] == Plus @@ Times @@@ f]; Select[Range[2, 10^4], q] (* Amiram Eldar, Nov 03 2024 *)
PROG
(PARI) is(k) = if(k > 1, my(f = factor(k)); f[1, 1] * f[#f~, 1] == f[, 1]~ * f[, 2], 0); \\ Amiram Eldar, Nov 03 2024
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Jul 18 2003
STATUS
approved