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Triangle read by rows: T(m,n) = parity of 0^n + 0^m, n = 0,1,2,3 ..., m = 0,1,2,3, ... n.
9

%I #20 Aug 22 2018 11:12:00

%S 0,1,0,1,0,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,0,

%T 0,0,1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,1,0,

%U 0,0,0,0,0,0,0,0,0,0,1

%N Triangle read by rows: T(m,n) = parity of 0^n + 0^m, n = 0,1,2,3 ..., m = 0,1,2,3, ... n.

%C Parity of the sums of two powers of any even number.

%H Michael De Vlieger, <a href="/A073424/b073424.txt">Table of n, a(n) for n = 0..11475</a> (rows 0 <= n <= 150).

%H Franck Ramaharo, <a href="https://arxiv.org/abs/1805.10680">A generating polynomial for the pretzel knot</a>, arXiv:1805.10680 [math.CO], 2018.

%F a(n) = parity [ (2k)^n + (2k)^m, n = 0, 1, 2, 3 ..., m = 0, 1, 2, 3, ... n ]

%F T(n,0) = 1- 0^n, T(n,k) = 0 for k>0. - _Philippe Deléham_, Feb 11 2012

%F G.f.: Theta_2(0,sqrt(x))/(2*x^(1/8))-1, where Theta_2 is a Jacobi theta function. - _Robert Israel_, Mar 01 2016

%e a(3) = 1 because (2k)^2 + (2k)^0 = 4k^2 + 1 is odd.

%e Triangle begins :

%e 0

%e 1, 0

%e 1, 0, 0

%e 1, 0, 0, 0

%e 1, 0, 0, 0, 0

%e 1, 0, 0, 0, 0, 0

%e 1, 0, 0, 0, 0, 0, 0

%e 1, 0, 0, 0, 0, 0, 0, 0

%e 1, 0, 0, 0, 0, 0, 0, 0, 0

%e 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 - _Philippe Deléham_, Feb 11 2012

%p 0, seq(op([1,0$n]), n=1..20); # _Robert Israel_, Mar 01 2016

%t Array[If[# == 1, {0}, PadRight[{1}, #]] &, 14] // Flatten (* or *)

%t Unprotect[Power]; Power[0, 0] = 1; Protect[Power]; Table[0^m + 0^n - 2 Boole[m == n == 0], {n, 0, 14}, {m, 0, n}] // Flatten (* _Michael De Vlieger_, Aug 22 2018 *)

%Y Cf. A023531, A010054, A073423.

%K easy,nonn,tabl

%O 0,1

%A _Jeremy Gardiner_, Jul 30 2002