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%I
%S 434,8575,8825
%N Solutions to sigma(x)+2=sigma(x+2) other than the smaller of twin primes.
%C This sequence together with A001359 gives the solutions of sigma(x)+2=sigma(x+2).
%D Sivaramakrishnan, R. (1989): Classical Theory of Arithmetical Functions, M. Dekker Inc., New York-Basel, p. 81, Problem 12.
%D These 3 solutions are from Makowski, according to Sivaramakrishnan, R. (1989).
%e sigma(434)+2=770=sigma(434+2), so 434 is in the sequence.
%o (PARI) is(n)=sigma(n+2)==sigma(n)+2&&!isprime(n) \\ _Charles R Greathouse IV_, Feb 13 2013
%Y Cf. A000203, A001359, A054799.
%K nonn,bref
%O 1,1
%A _Jud McCranie_, Dec 27 1999
%E No others < 4290000000.
%E No others < 50000000000. [From _Charles R Greathouse IV_, Oct 19 2010]
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