A053231 - OEIS

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A053231

First differences between n for which sigma(n) < sigma(n+1), which are not 2.

1, 1, 4, 1, 1, 1, 1, 4, 4, 1, 1, 1, 1, 4, 1, 1, 4, 1, 1, 4, 4, 1, 3, 4, 4, 1, 1, 1, 3, 1, 1, 4, 1, 1, 1, 1, 4, 1, 3, 1, 1, 4, 1, 1, 4, 1, 1, 4, 1, 1, 1, 1, 1, 1, 1, 3, 4, 1, 1, 1, 1, 1, 3, 4, 1, 1, 1, 1, 4, 4, 1, 1, 4, 4, 1, 1, 1, 3, 4, 1, 1, 1, 1, 4, 1, 1, 1, 1, 4, 1, 3, 1, 3, 4, 4, 1, 1, 1, 1, 4, 1, 1, 4, 1, 1 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,3`
	FORMULA	`The expansion of A053230 excluding 2's. a(n) = A053230(A053232(n)).`
	MAPLE	with(numtheory): f := [seq( `if`((sigma(i+1) > sigma(i)), i, print( )), i=1..5000)]; seq( `if`(f[i+1] - f[i] <> 2, f[i+1] - f[i], print( )), i=1..2000);
	CROSSREFS	`Cf. A000203, A053224, A053230, A053232, A053233, A053234, A053235, A053236, A053237.` `Sequence in context: A010326 A196879 A193349 * A066701 A046563 A046591` `Adjacent sequences: A053228 A053229 A053230 * A053232 A053233 A053234`
	KEYWORD	`nonn`
	AUTHOR	`Asher Auel (asher.auel(AT)reed.edu) Jan 10, 2000`

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Last modified February 17 04:58 EST 2012. Contains 205985 sequences.