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%I #11 Apr 29 2023 08:10:03
%S 20,42,156,342,930,1806,3660,5256,10506,11772,19182,22650,32580,37056,
%T 39402,52212,57840,73170,79806,97656,121452,176820,187056,213906,
%U 273006,325470,360600,382542,412806,436260,656910,676506,686412,737022,778806
%N a(n) = (p+2)!/p! where p is the n-th lesser twin prime, A001359(n).
%H Harvey P. Dale, <a href="/A126251/b126251.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = 2*A082669(n).
%p ZL:=[]:for p from 1 to 1653 do if (isprime(p) and isprime(p+2)) then ZL:=[op(ZL),((p+2)!/p!)]; fi; od; print(ZL);
%t #[[2]]!/#[[1]]!&/@Select[Partition[Prime[Range[200]],2,1],#[[2]]-#[[1]] == 2&] (* _Harvey P. Dale_, Feb 16 2020 *)
%Y Cf. A001359, A082669.
%Y Subsequence of A002378.
%K easy,nonn
%O 1,1
%A _Zerinvary Lajos_, Mar 08 2007
%E Name edited by _Michel Marcus_, Apr 29 2023
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