A158915 - OEIS

A158915

Least number k such that there is an m > k with sigma_n(k) = sigma_n(m).

2, 6, 6, 184926 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`0,1`
	COMMENTS	`It is easy to verify the first three terms using sequences A000005, A000203, and A001157. The first term of A131908 gives a(3). The a(4) term is greater than 10^8. Does a(n) exist for all n?`
	LINKS	`Table of n, a(n) for n=0..3.`
	EXAMPLE	`sigma_0(2)=sigma_0(3); sigma_1(6)=sigma_1(12); sigma_2(6)=sigma_2(7); sigma_3(184926)=sigma_3(194315).`
	CROSSREFS	`Sequence in context: A279841 A219195 A212223 * A257478 A243523 A011044` `Adjacent sequences: A158912 A158913 A158914 * A158916 A158917 A158918`
	KEYWORD	`more,nonn`
	AUTHOR	`T. D. Noe, Mar 30 2009`
	STATUS	`approved`

Last modified May 25 14:51 EDT 2022. Contains 354071 sequences. (Running on oeis4.)