The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A360328 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A360328

Numbers k such that A360327(k) > 2*k.
(history; published version)

#14 by Michael De Vlieger at Sat Feb 04 14:14:37 EST 2023

STATUS

reviewed

approved

#13 by Andrew Howroyd at Sat Feb 04 12:27:52 EST 2023

STATUS

proposed

reviewed

#12 by Amiram Eldar at Sat Feb 04 02:25:10 EST 2023

STATUS

editing

proposed

#11 by Amiram Eldar at Sat Feb 04 02:23:18 EST 2023

LINKS

Amiram Eldar, <a href="/A360328/b360328.txt">Table of n, a(n) for n = 1..1000</a>

STATUS

approved

editing

#10 by N. J. A. Sloane at Fri Feb 03 16:34:27 EST 2023

STATUS

proposed

approved

#9 by Jon E. Schoenfield at Fri Feb 03 07:17:11 EST 2023

STATUS

editing

proposed

#8 by Jon E. Schoenfield at Fri Feb 03 07:16:55 EST 2023

COMMENTS

The abundancy index of numbers in A076610 (i.e., numbers whose prime factors are only prime-indexed primes) is bounded by P = Product_{p in A006450} p/(p-1) which seems to be less than 4 (see A076610). Therefore, there are no terms k of A076610 with sigma(k) >= 4*k, or equivalently, no even terms in this sequences, sequence, and all the terms of this sequence are in A076610. Also, assuming that P < 15/4 = 3.75, there are no terms in this sequence that are coprime to 15.

STATUS

proposed

editing

#7 by Amiram Eldar at Fri Feb 03 05:35:43 EST 2023

STATUS

editing

proposed

#6 by Amiram Eldar at Fri Feb 03 05:31:26 EST 2023

CROSSREFS

Subsequence Intersection of A005101, (or A005231 ) and A076610.

#5 by Amiram Eldar at Fri Feb 03 05:30:50 EST 2023

COMMENTS

Includes all the abundant (A005101) terms of A076610.