A026969 a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026637.

1, 10, 75, 372, 1796, 7796, 33352, 138790, 571995, 2334558, 9473195, 38258984, 153981400, 618042736, 2475405456, 9897862062, 39523226642, 157650156506, 628287555844, 2502170730172, 9959281642416, 39622214018100, 157575049910690, 626477638980782, 2490112612092175

Offset: 3

Author

Clark Kimberling

Keywords

• nonn

Extensions

More terms from Sean A. Irvine, Oct 20 2019