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 A225684 Nonpalindromic numbers n with property that the sum of the reversed divisors of n is equal to n+1. 0
 965, 8150, 12966911, 625261742 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Palindromes are excluded because palindromic primes automatically have this property, and palindromic nonprimes never have it. Call a number "quasi-perfect" or "slightly excessive" if sigma(n) = 2n+1 (cf. A000203). It is conjectured that no quasi-perfect number exists. The present sequence is a variation that certainly has at least four terms. a(5) > 10^11. - Donovan Johnson, May 26 2013 LINKS Jason Earls, All About Reversed Slightly Excessive Numbers Eric Weisstein's World of Mathematics, Quasi-perfect number EXAMPLE The divisors of 965 are 1, 5, 193, 965, and reversing and adding produces 1 + 5 + 391 + 569 = 966. CROSSREFS Cf. A069192, A069250, A000203. Sequence in context: A267996 A093232 A252259 * A186468 A014363 A260291 Adjacent sequences:  A225681 A225682 A225683 * A225685 A225686 A225687 KEYWORD nonn,base,more AUTHOR N. J. A. Sloane, May 19 2013 EXTENSIONS a(4) from Donovan Johnson, May 19 2013 STATUS approved

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Last modified July 17 02:10 EDT 2019. Contains 325092 sequences. (Running on oeis4.)