A129598 a(n) = n * A111089(n).

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).

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000

G. Guninski, List of automatically found conjectural relations between this and other sequences

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.

Cf. also A050399, A089966, A111089, A072995.

Sequence in context: A367726 A033149 A131094 * A256017 A125752 A103147

Adjacent sequences: A129595 A129596 A129597 * A129599 A129600 A129601

Keyword

nonn

Author

Antti Karttunen, May 01 2007

Status

approved