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Triangle of Narayana numbers mod 2, T(n,k) = A001263(n,k) mod 2.
4

%I #6 Oct 10 2013 08:04:32

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

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

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

%N Triangle of Narayana numbers mod 2, T(n,k) = A001263(n,k) mod 2.

%H Reinhard Zumkeller, <a href="/A166360/b166360.txt">Rows n = 1..120 of triangle, flattened</a>

%e Triangle begins:

%e 1

%e 1 1

%e 1 1 1

%e 1 0 0 1

%e 1 0 0 0 1

%e 1 1 0 0 1 1

%e 1 1 1 1 1 1 1

%e 1 0 0 0 0 0 0 1

%e 1 0 0 0 0 0 0 0 1

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

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

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

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

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

%e 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1

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

%e ....

%o (PARI) p = 2; s=14; NT = matrix(s,s,n,k, binomial(n-1, k-1)*binomial(n, k-1)/k);

%o NTMP = matrix(s,s,n,k, NT[n,k]%p);

%o for(n=1,s,for(k=1,n,print1(NTMP[n,k]," "));print())

%o (Haskell)

%o a166360 n k = a166360_tabl !! (n-1) !! (k-1)

%o a166360_row n = a166360_tabl !! (n-1)

%o a166360_tabl = map (map (flip mod 2)) a001263_tabl

%o -- _Reinhard Zumkeller_, Oct 10 2013

%Y Cf. A001263, A047999, A007318.

%Y Cf. A230116 (rows seen as binary numbers).

%K easy,nonn,tabl

%O 1,1

%A _Gerald McGarvey_, Oct 12 2009