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%I #3 Mar 30 2012 18:51:00
%S 0,3,6,10,14,19,24,30,36,45,52,60,67,76,86,96,105,117,127,138,151,162,
%T 176,189,203,216,230,246,262,277,292,308,325,343,362,376,398,417,435,
%U 451,473,491,515,535,557,579,599,622,646,668,691,712,737,764,788,815
%N Sums of rows of the triangle in A139325.
%C a(n) = Sum(A139325(n,k): 1<=k<=n).
%F a(n) = A000720(2*n^2 - 1) - 1.
%e a(4)=#{3,5,7}+#{11,13}+#{17,19,23}+#{29,31}}=3+2+3+2}=10:
%e ..1 ...3 ...5 ...7 ... primes in first row = {3,5,7},
%e ..9 ..11 ..13 ..15 ... primes in 2nd row = {11,13},
%e .17 ..19 ..21 ..23 ... primes in 3rd row = {17,19},
%e .25 ..27 ..29 ..31 ... primes in 4th row = {29,31}.
%Y Cf. A038107.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Apr 14 2008
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