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%I #17 Jul 30 2021 04:46:32
%S 1,1,0,1,0,0,1,1,0,0,1,1,0,0,1,0,0,1,1,1,1,1,0,0,0,1,0,0,1,1,1,3,2,2,
%T 1,1,0,1,0,0,0,1,0,0,1,1,1,3,4,4,6,5,5,3,2,0,0,0,0,0,0,0,0,1,0,0,1,1,
%U 1,3,4,7,9,15,17,22,14,16,5,4,0,1,0,0,0
%N Triangle read by rows: T(n,k) is the number of planar graphs with n >= 1 nodes and 0 <= k <= binomial(n,2) edges, all degrees even.
%H Sean A. Irvine, <a href="/A049340/b049340.txt">Table of n, a(n) for n = 1..231, rows 1..11 flattened</a>
%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a049/A049340.java">Java program</a> (github)
%e Triangle begins:
%e 1;
%e 1, 0;
%e 1, 0, 0, 1;
%e 1, 0, 0, 1, 1, 0, 0;
%e 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 0;
%e 1, 0, 0, 1, 1, 1, 3, 2, 2, 1, 1, 0, 1, 0, 0, 0;
%e ...
%Y Rows sums give A049339.
%Y Cf. A000944, A021103, A003094, A049334.
%K nonn,tabf,easy,nice
%O 1,32
%A _Brendan McKay_
%E Entry revised by _Sean A. Irvine_, Jul 29 2021
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