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a(n)=m-k where x^2+x+41=m-th prime and x^2-x+41=k-th prime.
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%I #5 Mar 30 2012 18:52:39

%S 0,1,1,1,2,2,3,2,5,2,4,4,5,3,6,6,5,4,7,6,7,7,5,7,8,9,7,7,8,9,8,10,10,

%T 8,10,10,8,9,12,11,12,10,14,14,15,15,13,12,13,13,16,16,14,17,13,14,15,

%U 17,13,20,15,15,18,18,17,18,22,14,16,25,21,20,20,24,19,25,21,22,20,24,28

%N a(n)=m-k where x^2+x+41=m-th prime and x^2-x+41=k-th prime.

%e a(1)=13-13=0 where 0^2+0+41=41=13th prime and 0^2-0+41=41=13th prime; a(2)=14-13=1 where 1^2+1+41=43=14th prime and 1^2-1+41=41=13th prime; a(3)=15-14=1 where 2^2+2+41=47=15th prime and 2^2-2+41=43=14th prime; a(4)=16-15=1 where 3^2+3+41=53=16th prime and 3^2-3+41=47=15th prime.

%Y Cf. A005846.

%K nonn

%O 1,5

%A _Juri-Stepan Gerasimov_, Feb 23 2010

%E a(7), a(11) etc. corrected and sequence extended by _R. J. Mathar_, Mar 01 2010