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%I #8 Mar 12 2014 16:36:46
%S 3,5,11,13,31,241,337,601,6481,14401,19441,45361,100801,176401,
%T 1088641,18144001,32659201,50803201,72576001,199584001,958003201,
%U 1077753601,2155507201,2395008001,2594592001,56043187201,124540416001,647610163201
%N Primes in the triangle defined by T(0,c)=1, T(1,c)=c, T(r,1)=1 and T(r,c) = T(r,c-1)+ c*(r-1)!.
%e The host triangle T(r,c), defined recursively, starts in row r=0 with columns 1<=c<=r as:
%e 1;
%e 1,3;
%e 1,5,11;
%e 1,13,31,55;
%e 1,49,121,217,337;
%e 1,241,601,1081,1681,2401;'
%e ...
%e The primes in the triangle enter the sequence, sorted in natural order. - R. J. Mathar, Sep 11 2011
%t a[0, 0] = 1; a[1, 0] = 1; a[n_, 1] := a[n, 1] = n; a[1, m_] := a[1, m] = 1 a[n_, m_] := a[n, m] = a[n - 1, m] + (m - 1)!*n; aa = Delete[Union[Flatten[Table[Table[If[PrimeQ[a[n, m]] == True, a[n, m], 0], {n, 1, m}], {m, 0, 20}]]], 1]
%K nonn
%O 0,1
%A _Roger L. Bagula_, Apr 05 2005