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%I #33 Jan 26 2021 02:37:10
%S 965,8150,12966911,625261742
%N Nonpalindromic numbers n with property that the sum of the reversed divisors of n is equal to n+1.
%C Palindromes are excluded because palindromic primes automatically have this property, and palindromic nonprimes never have it.
%C 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.
%C a(5) > 10^11. - _Donovan Johnson_, May 26 2013
%C a(5) > 10^12. - _Giovanni Resta_, Aug 19 2019
%H Jason Earls, <a href="http://voices.yahoo.com/all-reversed-slightly-excessive-numbers-1315225.html">All About Reversed Slightly Excessive Numbers</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/QuasiperfectNumber.html">Quasi-perfect number</a>
%e The divisors of 965 are 1, 5, 193, 965, and reversing and adding produces 1 + 5 + 391 + 569 = 966.
%o (Python)
%o from sympy import divisors
%o def ispal(n): s = str(n); return s == s[::-1]
%o def ok(n):
%o return not ispal(n) and n+1 == sum(int(str(d)[::-1]) for d in divisors(n))
%o print([m for m in range(10**4) if ok(m)]) # _Michael S. Branicky_, Jan 25 2021
%Y Cf. A069192, A069250, A000203.
%K nonn,base,more
%O 1,1
%A _N. J. A. Sloane_, May 19 2013
%E a(4) from _Donovan Johnson_, May 19 2013
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