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%I #5 Oct 16 2022 09:18:49
%S 5,13,17,29,41,61,73,101,109,137,149,181,193,197,229,241,269,281,313,
%T 349,421,433,461,521,569,601,617,641,661,809,821,829,857,881,1021,
%U 1033,1049,1061,1093,1153,1229,1277,1289,1301,1321,1429,1453,1481,1489,1609
%N Twin primes of form 4k+1.
%p a[1]:=5:i:=2:for k from 6 to 3000 do if isprime(k) and isprime(k+2) then b:=k:c:=k+2: if b mod 4 = 1 then a[i]:=b:i:=i+1 fi: if c mod 4 = 1 then a[i]:=c:i:=i+1 fi:fi od: seq(a[n],n=1..i-1);
%t Select[Union[Flatten[Select[Partition[Prime[Range[300]],2,1],#[[2]]-#[[1]]==2&]]],Mod[ #,4]==1&] (* _Harvey P. Dale_, Oct 16 2022 *)
%Y Cf. A122564, A122565, A001097.
%K nonn
%O 1,1
%A _Miklos Kristof_, Sep 27 2006
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