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Triangle read by rows: T(n,k) is the number of connected graphs on n vertices having independence number k.
8

%I #12 Feb 20 2020 14:12:57

%S 1,1,0,1,1,0,1,4,1,0,1,11,8,1,0,1,34,63,13,1,0,1,103,524,205,19,1,0,1,

%T 405,5863,4308,513,26,1,0,1,1892,100702,135563,21782,1105,34,1,0,1,

%U 12166,2880002,7161399,1576634,84185,2140,43,1,0,1,105065,138772607,652024627,203380116,12140094,274156,3845,53,1,0

%N Triangle read by rows: T(n,k) is the number of connected graphs on n vertices having independence number k.

%C Bivariate inverse Euler transform of A263341. This sequence can be derived from A263341 because the independence number of a disconnected graph is the sum of the independence numbers of its components. - _Andrew Howroyd_, Feb 19 2020

%H Andrew Howroyd, <a href="/A294490/b294490.txt">Table of n, a(n) for n = 1..91</a> (first 13 rows derived from Brendan McKay data in A263341)

%e Triangle begins:

%e 1;

%e 1, 0;

%e 1, 1, 0;

%e 1, 4, 1, 0;

%e 1, 11, 8, 1, 0;

%e 1, 34, 63, 13, 1, 0;

%e 1, 103, 524, 205, 19, 1, 0;

%e 1, 405, 5863, 4308, 513, 26, 1, 0;

%e ...

%Y Columns 2..5 are A243781, A243782, A243783, A243784.

%Y Row sums give A001349.

%Y Cf. A263341 (not necessarily connected).

%K nonn,tabl

%O 1,8

%A _Andrew Howroyd_, Oct 31 2017

%E Terms a(56) and beyond derived from A263341 added by _Andrew Howroyd_, Feb 19 2020