A116031 - OEIS

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A116031

sigma(n)-phi(n) and sigma(n)+phi(n) are two palindromes greater than 2.

4, 388, 403, 10010, 11481, 12215, 41242, 42173, 44243, 223261, 223487, 403303, 2302031, 3288877, 3490447, 32605627, 40077553, 40162802, 42311323, 44044043, 117426509, 222613051, 230777581, 232075811, 287772226, 307222207, 327067459 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	LINKS	`Table of n, a(n) for n=1..27.`
	EXAMPLE	`sigma(3288877)-phi(3288877) = 44444 and` `sigma(3288877)+phi(3288877)=6577756.`
	CROSSREFS	`Cf. A115897, A116030.` `Sequence in context: A006237 A181044 A339449 * A115049 A307929 A202172` `Adjacent sequences: A116028 A116029 A116030 * A116032 A116033 A116034`
	KEYWORD	`nonn,base`
	AUTHOR	`Giovanni Resta, Feb 13 2006`
	EXTENSIONS	`a(15)-a(27) from Donovan Johnson, Feb 05 2010`
	STATUS	`approved`

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Last modified December 10 18:11 EST 2023. Contains 367717 sequences. (Running on oeis4.)