A228057 Odd numbers of the form p * m^2, where p is prime and m > 1.

27, 45, 63, 75, 99, 117, 125, 147, 153, 171, 175, 207, 243, 245, 261, 275, 279, 325, 333, 343, 363, 369, 387, 405, 423, 425, 475, 477, 507, 531, 539, 549, 567, 575, 603, 605, 637, 639, 657, 675, 711, 725, 747, 775, 801, 833, 845, 847, 867, 873, 891, 909, 925

Offset

1,1

Comments

This sequence is the second step toward candidates for odd perfect numbers, A228058.

Links

T. D. Noe, Table of n, a(n) for n = 1..10000

Mathematica

nn = 1000; Union[Select[Flatten[Table[p*n^2, {p, Prime[Range[2, PrimePi[nn/4]]]}, {n, 3, Sqrt[nn/2], 2}]], # < nn &]]

Prog

(Haskell)
a228057 n = a228057_list !! (n-1)
a228057_list = filter odd a228056_list -- Reinhard Zumkeller, Aug 14 2013

Crossrefs

Cf. A228056, A228058.

Sequence in context: A046340 A046316 A046373 * A113481 A328897 A369979

Adjacent sequences: A228054 A228055 A228056 * A228058 A228059 A228060

Keyword

nonn

Author

T. D. Noe, Aug 13 2013

Status

approved