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%I #4 Dec 05 2013 19:56:35
%S 1,2,3,3,4,5,4,5,6,10,5,6,7,8,9,6,7,8,9,10,11,7,8,9,10,11,12,14,8,9,
%T 10,11,12,14,15,16,9,10,11,12,13,14,15,16,21,10,11,12,13,14,15,17,18,
%U 19,20,11,12,13,14,15,16,17,18,19,20,21,12,13,14,15,16,17,18,19,20,21,22,23
%N Triangle read by rows, in which n-th row contains n numbers starting with n and in increasing order such that the product of the terms + 1 gives the smallest such prime.
%C It is not always the case that the first n-1 terms are n,n+1, n+2, ... 2n-2 etc. and then the last term chosen to yield a prime. The choice of the terms is the one that yields the least prime.
%e 1
%e 2 3
%e 3 4 5
%e 4 5 6 10
%e 5 6 7 8 9
%e ...
%e a(22)..a(28)=7,8,9,10,11,12,14 is the strictly increasing sequence that yields the smallest prime A089307(7)=9313921 of the form 7*n2*n3*..*n7+1, 7<n2<...<n7.
%Y Cf. A089307.
%K nonn,tabl
%O 1,2
%A _Amarnath Murthy_, Nov 01 2003
%E More terms from _Hugo Pfoertner_, Apr 06 2004
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