login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A328738 Numbers k such that at least one of sopfr(k-1) and sopfr(k+1) is greater than or equal to 4*sopfr(k). 2
48, 54, 60, 66, 70, 72, 78, 80, 84, 88, 90, 96, 98, 100, 102, 104, 108, 110, 112, 114, 126, 128, 130, 132, 135, 136, 138, 140, 147, 150, 152, 156, 162, 165, 168, 174, 180, 182, 190, 192, 195, 196, 198, 200, 210, 222, 224, 225, 228, 230, 232, 234 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

k-1 or k+1 or both have sums of prime factors at least 4 times the sum of prime factors of k.

LINKS

Table of n, a(n) for n=1..52.

CROSSREFS

Cf. A001414, A328736, A328737.

Sequence in context: A296872 A357429 A258694 * A067191 A080854 A255267

Adjacent sequences: A328735 A328736 A328737 * A328739 A328740 A328741

KEYWORD

nonn

AUTHOR

Robert Bilinski, Oct 26 2019

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 1 21:09 EST 2022. Contains 358484 sequences. (Running on oeis4.)