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Smallest prime == 1 (mod (least common multiple of next n numbers)).
1

%I #12 Mar 15 2018 04:11:55

%S 2,7,61,2521,120121,9767521,248648401,5083737121,2679757320241,

%T 1105598948454001,531670984004161,343973251893070801,

%U 65801152591041067201,1102084393565113358401,710288051968384142853601

%N Smallest prime == 1 (mod (least common multiple of next n numbers)).

%H Harvey P. Dale, <a href="/A088107/b088107.txt">Table of n, a(n) for n = 1..200</a>

%e a(3) = 61; 61 == 1 (mod 60), 60 = lcm(4,5,6).

%t getp[n_]:=Module[{p=n+1},While[!PrimeQ[p],p=p+n];p]; getp/@With[{rr=15}, LCM@@#&/@TakeList[Range[(rr(rr+1))/2],Range[rr]]] (* Requires Mathematica version 11 or later *) (* _Harvey P. Dale_, Dec 19 2017 *)

%Y Cf. A088106.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Sep 24 2003

%E More terms from _David Wasserman_, Jul 19 2005