A116192 Triangle T(n,k), 0<=k<=n : T(n,k)is smallest number such that T(n,k)>T(n-1,k-1), T(n,k)>T(n-1,k), T(n,k)and T(n-1,k-1)+T(n-1,k) have the same parity, T(0,0)=1 .

1, 3, 3, 5, 4, 5, 7, 7, 7, 7, 9, 8, 8, 8, 9, 11, 11, 10, 10, 11, 11, 13, 12, 13, 12, 13, 12, 13, 15, 15, 15, 15, 15, 15, 15, 15, 17, 16, 16, 16, 16, 16, 16, 16, 17, 19, 19, 18, 18, 18, 18, 18, 18, 19, 19, 21, 20, 21, 20, 20, 20, 20, 20, 21, 20, 21, 23, 23, 23, 23, 22, 22, 22, 22

Offset

0,2

Comments

Sequence read mod 2 gives A047999 .

Links

Table of n, a(n) for n=0..73.

Formula

Sum_{k, 0<=k<=n}T(n,k)=A128806(n). T(2n,n)=A008574(n). T(n,k)=2n+1 if binomial(n,k) is odd, T(n,k)=2n if binomial(n,k) is even .

Example

Triangle begins:
1;
3, 3;
5, 4, 5;
7, 7, 7, 7;
9, 8, 8, 8, 9;
11, 11, 10, 10, 11, 11;
13, 12, 13, 12, 13, 12, 13;
15, 15, 15, 15, 15, 15, 15, 15 ;...

Crossrefs

Diagonals : A005408, A014601.

Sequence in context: A072820 A204004 A131950 * A090104 A388542 A333822

Adjacent sequences: A116189 A116190 A116191 * A116193 A116194 A116195

Keyword

nonn,tabl

Author

Philippe Deléham, Apr 08 2007

Status

approved