The sum of the numbers that are inside the contour of an n-story Christmas tree drawn at the top of the numerical pyramid containing the positive integers in natural order.
A358994
The sum of the numbers that are inside the contour of an n-story Christmas tree drawn at the top of the numerical pyramid containing the positive integers in natural order.
Terms
- a(0) =21a(1) =151a(2) =561a(3) =1503a(4) =3310a(5) =6396a(6) =11256a(7) =18466a(8) =28683a(9) =42645a(10) =61171a(11) =85161a(12) =115596a(13) =153538a(14) =200130a(15) =256596a(16) =324241a(17) =404451a(18) =498693a(19) =608515a(20) =735546a(21) =881496a(22) =1048156a(23) =1237398a(24) =1451175a(25) =1691521a(26) =1960551a(27) =2260461a(28) =2593528a(29) =2962110
External references
- oeis: A358994