A133981 Triangle read by rows: A000012 * A127701 + A127701 * A000012 - A000012 as infinite lower triangular matrices.

1, 4, 3, 5, 6, 5, 6, 7, 8, 7, 7, 8, 9, 10, 9, 8, 9, 10, 11, 12, 11, 9, 10, 11, 12, 13, 14, 13, 10, 11, 12, 13, 14, 15, 16, 15, 11, 12, 13, 14, 15, 16, 17, 18, 17, 12, 13, 14, 15, 16, 17, 18, 19, 20, 19, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 21, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 23

Offset

1,2

Comments

Row sums = A133694: (1, 7, 16, 28, 43, 61, ...).

Links

Table of n, a(n) for n=1..78.

Example

First few rows of the triangle:
   1;
   4,  3;
   5,  6,  5;
   6,  7,  8,  7;
   7,  8,  9, 10,  9;
   8,  9, 10, 11, 12, 11;
   9, 10, 11, 12, 13, 14, 13;
  10, 11, 12, 13, 14, 15, 16, 15;
  11, 12, 13, 14, 15, 16, 17, 18, 17;
  ...

Crossrefs

Cf. A127701, A133694.

Sequence in context: A280023 A170816 A336067 * A226211 A296413 A016701

Adjacent sequences: A133978 A133979 A133980 * A133982 A133983 A133984

Keyword

nonn,tabl

Author

Gary W. Adamson, Sep 30 2007

Extensions

a(26) = 13 corrected and more terms from Georg Fischer, Jun 07 2023

Status

approved