login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A056166 Numbers which are the product of distinct primes raised to prime powers. 7
1, 4, 8, 9, 25, 27, 32, 36, 49, 72, 100, 108, 121, 125, 128, 169, 196, 200, 216, 225, 243, 288, 289, 343, 361, 392, 441, 484, 500, 529, 675, 676, 800, 841, 864, 900, 961, 968, 972, 1000, 1089, 1125, 1152, 1156, 1225, 1323, 1331, 1352, 1369, 1372, 1444 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

EXAMPLE

200 is included because 200 = 2^3 * 5^2.

MATHEMATICA

{1}~Join~Select[Range[1500], AllTrue[FactorInteger[#][[All, -1]], PrimeQ] &] (* Michael De Vlieger, Aug 20 2017 *)

PROG

(PARI) is(n)=#select(e->!isprime(e), factor(n)[, 2])==0 \\ Charles R Greathouse IV, Sep 18 2015

CROSSREFS

Sequence in context: A261987 A158340 A259183 * A093771 A051676 A114129

Adjacent sequences:  A056163 A056164 A056165 * A056167 A056168 A056169

KEYWORD

nonn

AUTHOR

Leroy Quet, Aug 01 2000

EXTENSIONS

a(1) added, offset corrected by Charles R Greathouse IV, Sep 18 2015

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 19 15:08 EDT 2019. Contains 327198 sequences. (Running on oeis4.)