A048223 a(n)=T(n,1)+T(n,n), array T given by A048212.

4, 4, 11, 19, 29, 39, 54, 72, 89, 113, 137, 163, 189, 216, 254, 288, 323, 363, 402, 446, 495, 544, 593, 651, 710, 772, 835, 898, 964, 1036, 1106, 1185, 1263, 1341, 1420, 1504, 1591, 1681, 1770, 1860, 1963, 2063, 2165, 2271, 2378

Offset

1,1

Links

Table of n, a(n) for n=1..45.

Formula

a(n) = 2*A004979(n+1) - A004979(n) - 1. - Sean A. Irvine, Jun 05 2021

Crossrefs

Cf. A004979.

Sequence in context: A231064 A302516 A254205 * A358825 A214112 A211950

Adjacent sequences: A048220 A048221 A048222 * A048224 A048225 A048226

Keyword

nonn

Author

Clark Kimberling

Status

approved