A128703 Numbers of the form 5^k*p, where 1 <= k <= 5 and p is a prime different from 5.

10, 15, 35, 50, 55, 65, 75, 85, 95, 115, 145, 155, 175, 185, 205, 215, 235, 250, 265, 275, 295, 305, 325, 335, 355, 365, 375, 395, 415, 425, 445, 475, 485, 505, 515, 535, 545, 565, 575, 635, 655, 685, 695, 725, 745, 755, 775, 785, 815, 835, 865, 875, 895, 905

Offset: 1

Author

Klaus Brockhaus, Mar 26 2007

Keywords

• nonn

Comments

Auxiliary sequence for A128704 which gives the number of groups of order a(n).

Examples

			375 = 5^3*3 is a term.
		

Links

• Klaus Brockhaus, Table of n, a(n) for n=1..10000

Crossrefs

Cf. A128704, A000351 (powers of 5).

Programs

Magma

[ n: n in [1..910] | #t eq 2 and ((t[1, 1] lt 5 and t[1, 2] eq 1 and t[2, 1] eq 5 and t[2, 2] le 5) or (t[1, 1] eq 5 and t[1, 2] le 5 and t[2, 2] eq 1)) where t is Factorization(n) ];

Mathematica

With[{upto=1000},Select[Union[Flatten[5^Range[5] #&/@Drop[Prime[ Range[ PrimePi[ Ceiling[upto/5]]]],{3}]]],#<=upto&]] (* Harvey P. Dale, Jul 27 2011 *)