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%I #22 Apr 07 2015 13:51:57
%S 1,2,6,12,28,36,52,60,78,106,112,150,172,180,198,238,270,280,316,348,
%T 358,396,420,456,502,540,556,576,592,612,700,732,768,786,856,862,910,
%U 952,982,1020,1060,1068,1150,1162,1192,1212,1290,1398,1428,1438,1458
%N a(n) = prime(prime(n) - 1) - 1, where prime(n) is the n-th prime.
%H Charles R Greathouse IV, <a href="/A140853/b140853.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = A055003(n) - 1. - _N. J. A. Sloane_, Jul 31 2008
%F a(n) ~ n (log n)^2. - _Charles R Greathouse IV_, Apr 07 2015
%t Table[Prime[Prime[n - 1] - 1] - 1, {n, 2, 60}] (* _Vincenzo Librandi_, Apr 05 2015 *)
%o (PARI) apply(p->prime(p-1)-1, primes(100))
%Y Cf. A006093, A055003.
%K nonn,easy
%O 1,2
%A _Juri-Stepan Gerasimov_, Jul 30 2008
%E Corrected (382 replaced by 396) and extended by _R. J. Mathar_, Apr 27 2010
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