A089966 -id:A089966 - cp's OEIS frontend

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

Antti Karttunen, May 01 2007

nonn

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).

Antti Karttunen, Table of n, a(n) for n = 1..10000
G. Guninski, List of automatically found conjectural relations between this and other sequences

Row 2 of A129595.
Essentially the same as A253560, except that here we have a(1) = 2.
Cf. also A050399, A089966, A111089, A072995.

Join[{2},Table[n*Last@(First/@FactorInteger[n]),{n,2,200}]] (* Vladimir Joseph Stephan Orlovsky, Apr 08 2011 *)

a(1) = 2; for n >= 2, a(n) = A253560(n).

A089967 Numbers n such that Omega(n) = gpf(n) mod spf(n), where Omega=A001222, gpf=A006530 and spf=A020639.

Original entry on oeis.org

1, 15, 33, 35, 51, 69, 85, 87, 123, 141, 143, 159, 161, 177, 185, 213, 235, 249, 259, 267, 303, 321, 323, 325, 335, 339, 393, 411, 447, 455, 485, 501, 519, 533, 535, 537, 553, 573, 575, 591, 635, 681, 685, 699, 715, 717, 749, 753, 771, 785, 789, 805, 807

Offset: 1

Reinhard Zumkeller, Nov 17 2003

nonn

A069859(a(n)) = A001222(a(n));

A064900 is a subsequence.

Cf. A089966.

cp's OEIS Frontend

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

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