A074487 - OEIS

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A074487

a(1)=1, then "jump over next square": a(n) = 2*(a(n-1)+1)^2-a(n-1).

1, 7, 121, 29647, 1757978161, 6180974434379818327, 76408889916913830205838054898189612841, 11676636916670111980512852400247542904848802859324947344926081051625513021087 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,2`
	COMMENTS	`The rule "jump over next something" can be varied, see A075694, A075695.`
	LINKS	`Table of n, a(n) for n=1..8.`
	FORMULA	`a(1)=1, a(n) = 2*(a(n-1)+1)^2 - a(n-1).`
	EXAMPLE	`a(1)=1; next square is (a(1)+1)^2=4; "jump over" it: 4+(4-1)=7; a(2)=7; next square is (a(2)+1)^2=64; "jump over" it: 64+(64-7)=121.`
	MAPLE	`a(1) := 1; a(n) := 2*(a(n-1)+1)^2-a(n-1);`
	CROSSREFS	`Cf. A075694, A075695.` `Sequence in context: A211103 A012103 A012086 * A192566 A322090 A360337` `Adjacent sequences: A074484 A074485 A074486 * A074488 A074489 A074490`
	KEYWORD	`easy,nonn`
	AUTHOR	`Zak Seidov, Sep 26 2002`
	STATUS	`approved`

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Last modified March 28 08:01 EDT 2023. Contains 361579 sequences. (Running on oeis4.)