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A129598
a(n) = n * A111089(n).
4
2, 4, 9, 8, 25, 18, 49, 16, 27, 50, 121, 36, 169, 98, 75, 32, 289, 54, 361, 100, 147, 242, 529, 72, 125, 338, 81, 196, 841, 150, 961, 64, 363, 578, 245, 108, 1369, 722, 507, 200, 1681, 294, 1849, 484, 225, 1058, 2209, 144, 343, 250, 867, 676, 2809, 162, 605
OFFSET
1,1
COMMENTS
Conjecture: differs from A050399 at the positions given by A089966. E.g., a(15)=75, instead of A050399(15)=225, a(30)=150, instead of A050399(30)=450, a(33)=363, instead of A050399(33)=1089, a(45)=225, instead of A050399(45)=1225. Conjecture 2: for all n > 1, a(n) divides A050399(n).
FORMULA
a(1) = 2; for n >= 2, a(n) = A253560(n).
MATHEMATICA
Join[{2}, Table[n*Last@(First/@FactorInteger[n]), {n, 2, 200}]] (* Vladimir Joseph Stephan Orlovsky, Apr 08 2011 *)
CROSSREFS
Row 2 of A129595.
Essentially the same as A253560, except that here we have a(1) = 2.
Sequence in context: A367726 A033149 A131094 * A256017 A125752 A103147
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 01 2007
STATUS
approved