OFFSET
1,1
LINKS
David A. Corneth, Table of n, a(n) for n = 1..10000 (first 1000 terms from Donovan Johnson)
EXAMPLE
12 = 2^2 * 3^1 and 2+2 = 3+1, so 12 is a term.
64800 = 2^5 * 3^4 * 5^2 and 2+5 = 3+4 = 5+2, so 64800 is a term.
212625 = 3^5 * 5^3 * 7^1 and 3+5 = 5+3 = 7+1, etc.
750141 = 3^7 * 7^3 and 3+7 = 7+3, etc.
The first term with three prime factors is 2160 = 2^4 * 3^3 * 5^1; the first with four is 13608000 = 2^6 * 3^5 * 5^3 * 7^1.
MATHEMATICA
fQ[n_] := Module[{f = FactorInteger[n]}, Length[f] > 1 && Length[Union[Plus @@@ f]] == 1]; Select[Range[2, 100000], fQ] (* T. D. Noe, Nov 21 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Carl R. White, Nov 17 2012
STATUS
approved