login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A036321 Composite numbers n such that digits of prime factors of n are either 5 or 9. 2
25, 125, 295, 625, 1475, 2995, 3125, 3481, 7375, 14975, 15625, 17405, 35341, 36875, 74875, 78125, 87025, 176705, 184375, 205379, 299995, 358801, 374375, 390625, 435125, 479795, 497795, 883525, 921875, 1026895, 1499975, 1794005, 1871875 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

All terms are a product of at least two terms of A020468. - David A. Corneth, Oct 09 2020

LINKS

David A. Corneth, Table of n, a(n) for n = 1..10000

Index entries for sequences related to prime factors

MATHEMATICA

Select[Range[1872000], CompositeQ[#]&&SubsetQ[{5, 9}, Flatten[ IntegerDigits/@ FactorInteger[#][[All, 1]]]]&] (* Harvey P. Dale, Sep 17 2019 *)

CROSSREFS

Cf. A020468, A036302-A036325.

Sequence in context: A044357 A044738 A062672 * A289337 A211581 A226231

Adjacent sequences:  A036318 A036319 A036320 * A036322 A036323 A036324

KEYWORD

nonn,easy,base

AUTHOR

Patrick De Geest, Dec 15 1998

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 February 27 05:17 EST 2021. Contains 341649 sequences. (Running on oeis4.)