A128187 -id:A128187 - cp's OEIS frontend

A128188 Row sums of A128187.

1, 2, 3, 5, 5, 9, 7, 13, 10, 17, 12, 23, 14, 27, 18, 32, 20, 38, 22, 44, 26, 48, 28, 56, 31, 60, 35, 66, 37, 74, 39, 80, 43, 84, 47, 93, 49, 97, 53, 105, 55, 113, 57, 119, 63, 123, 65, 133, 68, 139, 72, 145, 74, 153, 78, 161, 82, 165, 84, 177, 86, 181, 92, 188, 96, 196, 98, 202, 102, 210

Offset: 1

Gary W. Adamson, Feb 17 2007

nonn

			a(6) = 9 = sum of row 6 terms of A128187: (3 + 3 + 1 + 1 + 1).

Cf. A000005, A128187.

A128188 := proc(n)
    add(A128187(n,k),k=1..n) ;
end proc; # R. J. Mathar, Apr 16 2013
with(numtheory): A128188:=n->add(tau(n+2-2*i), i=1..floor((n+2)/2)): seq(A128188(n), n=1..100); # Wesley Ivan Hurt, Jul 12 2015

a(n) = Sum_{k=1..n} A128187(n,k).

a(n) = Sum_{i=1..floor((n+2)/2)} d(n+2-2i), where d(n) is the number of divisors of n. - Wesley Ivan Hurt, Jul 12 2015

A128186 A051731 * A128174.

Original entry on oeis.org

1, 1, 1, 2, 0, 1, 1, 2, 0, 1, 2, 0, 1, 0, 1, 2, 2, 1, 1, 0, 1, 2, 0, 1, 0, 1, 0, 1, 1, 3, 0, 2, 0, 1, 0, 1, 3, 0, 2, 0, 1, 0, 1, 0, 1, 2, 2, 1, 1, 1, 1, 0, 1, 0, 1

Offset: 1

Gary W. Adamson, Feb 17 2007

Left column = A001227.
Row sums = A079247: (1, 2, 3, 4, 4, 7, 5, 8, 8, 10, ...).
A128187 = A128174 * A051731.

			First few rows of the triangle:
  1;
  1, 1;
  2, 0, 1;
  1, 2, 0, 1;
  2, 0, 1, 0, 1;
  2, 2, 1, 1, 0, 1;
  2, 0, 1, 0, 1, 0, 1;
  ...

Cf. A128174, A051731, A128187, A079247, A001227.

A051731 * A128174 as infinite lower triangular matrices.

cp's OEIS Frontend

A128188 Row sums of A128187.

Views

Author

Keywords

Examples

Crossrefs

Programs

Maple

Formula