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The n-th member of a twin prime pair minus 2*n.
1

%I #7 Feb 03 2022 13:30:36

%S 1,1,1,3,3,5,5,13,13,21,21,35,35,43,43,69,69,71,71,97,97,105,105,131,

%T 131,139,139,141,141,167,167,175,175,201,201,209,209,235,235,267,267,

%U 335,335,343,343,369,369,425,425,469,469,495,495,509,509,529,529,543

%N The n-th member of a twin prime pair minus 2*n.

%H Harvey P. Dale, <a href="/A161220/b161220.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n)=A001097(n)-A005843(n).

%e a(1) = 3-2*1=1. a(2) =5-2*2=1. a(3)=7-2*3=1. a(4)=11-2*4=3.

%t Module[{tp=Union[Flatten[Select[Partition[Prime[Range[150]],2,1],#[[2]]- #[[1]] == 2&]]]},#[[1]]-#[[2]]&/@Thread[{tp,2*Range[Length[tp]]}]] (* _Harvey P. Dale_, Feb 03 2022 *)

%Y Cf. A001097, A005843.

%K nonn

%O 1,4

%A _Juri-Stepan Gerasimov_, Jun 06 2009

%E Entries confirmed by _R. J. Mathar_, Jun 23 2009