A351158 - OEIS

A351158

Number of n X n symmetric 0-1 matrices where rows are sorted lexicographically and row sums are nondecreasing.

2, 5, 15, 56, 275, 1897, 18948 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	LINKS	`Table of n, a(n) for n=1..7.`
	CROSSREFS	`Sequence in context: A121392 A216388 A005976 * A187981 A334155 A348365` `Adjacent sequences: A351155 A351156 A351157 * A351159 A351160 A351161`
	KEYWORD	`nonn,hard,more`
	AUTHOR	`Max Alekseyev, Feb 02 2022`
	STATUS	`approved`

Last modified February 4 05:49 EST 2023. Contains 360046 sequences. (Running on oeis4.)