A145774 - OEIS

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A145774

Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only either two adjacent vertically or two adjacent horizontally.

1, 3, 5, 18, 124, 889, 9624, 117592, 3086899, 71342470, 3940302454, 162484045629, 19765145478158, 1482360209667114, 393627814809408705, 53489489176352337875, 30927278141339388397696, 7617052120730650394236371 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,2`
	LINKS	`Table of n, a(n) for n=1..18.`
	CROSSREFS	`Sequence in context: A303684 A022489 A176749 * A348778 A270894 A272317` `Adjacent sequences: A145771 A145772 A145773 * A145775 A145776 A145777`
	KEYWORD	`nonn`
	AUTHOR	`R. H. Hardin, Oct 18 2008`
	STATUS	`approved`

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Last modified December 9 20:06 EST 2023. Contains 367693 sequences. (Running on oeis4.)