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 A116031 sigma(n)-phi(n) and sigma(n)+phi(n) are two palindromes greater than 2. 1
 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.)