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%I #10 Jun 23 2022 09:29:48
%S 2,23,37,53,67,97,131,173,223,233,263,277,307,337,409,457,509,563,593,
%T 613,631,653,797,853,877,1013,1039,1087,1129,1223,1259,1283,1297,1307,
%U 1423,1447,1471,1601,1613,1663,1693,1709,1783,1867,1913,1993,2017,2069
%N Largest non-twin prime < n-th and (n+1)-th twin primes.
%H Harvey P. Dale, <a href="/A144550/b144550.txt">Table of n, a(n) for n = 1..1000</a>
%F {A007510(k): nextprime(A007510(k)) in A077800}. - _R. J. Mathar_, May 01 2010
%p isA077800 := proc(n) isprime(n) and ( isprime(n+2) or isprime(n-2)) ; end proc:
%p isA007510 := proc(n) isprime(n) and not isA077800(n) ; end proc:
%p isA144550 := proc(n) isA007510(n) and isA077800( nextprime(n)) ; end proc:
%p for n from 2 to 2500 do if isA144550(n) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, May 01 2010
%t Module[{nn=400,tps},tps=Union[Flatten[Select[Partition[Prime[Range[nn]],2,1], #[[2]]-#[[1]] == 2&]]];Complement[NextPrime[#,-1]&/@tps,tps]] (* _Harvey P. Dale_, Jun 23 2022 *)
%Y Cf. A077800, A088175.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Dec 31 2008
%E Corrected (1993 inserted) by _R. J. Mathar_, May 01 2010
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