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Row 1 of prime separator array A129258.
2

%I #2 Mar 30 2012 18:57:10

%S 1,2,4,7,9,13,15,18,23,25,29,31,36,40,42,46,49,51,55,58,61,63,67,71,

%T 78,80,83,85,89,92,97,102,105,109,111,113,117,122,127,130,134,136,139,

%U 142,150,152,156,159,161,166,169,173,177,179,185,187,192,194,196,199

%N Row 1 of prime separator array A129258.

%C This contains the primes 2,7,13,23,29,31. A129260 contains all primes not here.

%F A129258 is the sequence T(n,1) defined as follows. T(1,1)=1. For n>=1, let S(n)={(i,j): 1<=i<=n and 1<=j<=n}. Once T(i,j) is defined on S(n), define T(1,n+1)=least positive integer (l.p.i.) not among T(i,j) for (i,j) in S(n); T(n+1,1)=l.p.i. not among T(i,j) for (i,j) in S(n) and not T(1,n+1); T(m,n+1)=T(m,1)*T(1,n+1) for m=2,3,...,n+1; T(n+1,m)=T(n+1,1)*T(1,m) for m=2,3,...,n+1.

%e Row 1 of the array A129258 with northwest corner

%e 1 2 4 7 9 13 15 18

%e 3 6 12 21 27 39 45 54

%e 5 10 20 35 45 65 75 90

%e 8 16 32 56 72 104 120 144

%e 11 22 44 77 99 143 165 198

%Y Cf. A129258, A129260.

%K nonn

%O 1,2

%A _Clark Kimberling_, Apr 06 2007