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a(n) = ((prime(n)-2)!+2) mod prime(n)# (cf. A002110).
2

%I #16 Dec 15 2018 08:34:59

%S 1,3,8,122,212,6932,450452,9189182,193993802,2677114442,116454478142,

%T 5415133233512,51945166943672,1521251317636052,562558737261811292,

%U 1229779565176982822,130356633908760178922,19227603501542126390702,4456958491657464897364262

%N a(n) = ((prime(n)-2)!+2) mod prime(n)# (cf. A002110).

%C Smallest positive residue modulo p_1*...*p_n (cf. A002110) of (p_n-2)!+2, where p_n=prime(n).

%C See comment in A245460.

%H Jens Kruse Andersen, <a href="/A245458/b245458.txt">Table of n, a(n) for n = 1..100</a>

%H V. Shevelev, <a href="http://arXiv.org/abs/0912.4006">Theorems on twin primes-dual case</a>, arXiv:0912.4006 (Sections 10,11,14-18)

%t a[n_] := Mod[(Prime[n]-2)! + 2, Product[Prime[i], {i, 1, n}]];

%t Array[a, 19] (* _Jean-François Alcover_, Dec 15 2018 *)

%o (PARI) a(n) = ((prime(n)-2)!+2) % prod(i=1, n, prime(i)) \\ _Jens Kruse Andersen_, Jul 22 2014

%Y Cf. A002110, A245457, A244570, A244571, A244572.

%K nonn

%O 1,2

%A _Vladimir Shevelev_, Jul 22 2014

%E More terms and simpler definition from _Jens Kruse Andersen_, Jul 22 2014