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%I #17 Dec 20 2015 09:18:58
%S 3,5,17,40,41,203,1949,2309,2711,2789,2801,3299,3329,3359,3917,4157,
%T 4217,4259,4637,5009,5021,5231,6449,6497,7757,8087,8219,8627,9419,
%U 9929,10007,10937,11777,12071,14321,15647,15971,16061,16901,18131,18251
%N Numbers n such that sigma(n+2) - sigma(n) = prime(n+1) - prime(n).
%C If n and n+2, prime(n) and prime(n+1) are twin primes, then n is in the sequence. But some values of n are composite.
%H Harry J. Smith, <a href="/A067062/b067062.txt">Table of n, a(n) for n = 1..1000</a>
%p with(numtheory); A067062:=n->`if`(sigma(n+2)-sigma(n)=ithprime(n+1)-ithprime(n),n,NULL); seq(A067062(n), n=1..20000); # _Wesley Ivan Hurt_, Nov 27 2013
%t okQ[n_]:=DivisorSigma[1,n+2]-DivisorSigma[1,n]==Prime[n+1]-Prime[n]; Select[Range[20000],okQ] (* _Harvey P. Dale_, May 24 2011 *)
%o (PARI) { default(primelimit, 4294965247); n=0; for (m=1, 10^10, if (sigma(m+2)-sigma(m) == prime(m+1)-prime(m), write("b067062.txt", n++, " ", m); if (n==1000, return)) ) } \\ _Harry J. Smith_, May 02 2010
%K nonn
%O 1,1
%A _Benoit Cloitre_, Feb 17 2002
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