A131307 (A127701 * A000012 + A000012(signed) * A127701) - A000012.

1, 2, 3, 3, 2, 5, 4, 5, 2, 7, 5, 4, 7, 2, 9, 6, 7, 4, 9, 2, 11, 7, 6, 9, 4, 11, 2, 13, 8, 9, 6, 11, 4, 13, 2, 15, 9, 8, 11, 6, 13, 4, 15, 2, 17, 10, 11, 8, 13, 6, 15, 4, 17, 2, 19

Offset

1,2

Comments

Row sums = A035608: (1, 5, 10, 18, 27, 39, 52, ...).

Links

Table of n, a(n) for n=1..55.

Formula

(A127701 * A000012 + A000012(signed) * A127701) - A000012; as infinite lower triangular matrices, where A000012(signed) = (1; -1,1; 1,-1,1; -1,1,-1,1; ...).

Example

First few rows of the triangle:
   1;
   2,  3;
   3,  2,  5;
   4,  5,  2,  7;
   5,  4,  7,  2,  9;
   6,  7,  4,  9,  2, 11;
   7,  6,  9,  4, 11,  2, 13;
   8,  9,  6, 11,  4, 13,  2, 15;
   9,  8, 11,  6, 13,  4, 15,  2, 17;
  10, 11,  8, 13,  6, 15,  4, 17,  2, 19;
  ...

Crossrefs

Cf. A000012, A127701, A035608.

Sequence in context: A131899 A095174 A376676 * A336168 A091813 A238114

Adjacent sequences: A131304 A131305 A131306 * A131308 A131309 A131310

Keyword

nonn,tabl,more

Author

Gary W. Adamson, Sep 30 2007

Status

approved