Statements (24)
| Predicate | Object |
|---|---|
| gptkbp:instanceOf |
integer sequence
|
| gptkbp:author |
gptkb:N._J._A._Sloane
|
| gptkbp:first_terms |
2
1 11 16 22 29 4 7 |
| gptkbp:form |
a(n) = a(n-1) + n
a(n) = binomial(n+2,2) - 1 a(n) = n(n+3)/2 |
| gptkbp:hasComments |
Also called the central polygonal numbers.
a(n) is the number of regions formed when n+1 lines are drawn in the plane so that no two are parallel and no three are concurrent. |
| gptkbp:hasKeyword |
easy
nice nonn |
| gptkbp:hasOEISLink |
https://oeis.org/A000124
|
| gptkbp:hasOEISTitle |
gptkb:Central_polygonal_numbers
|
| gptkbp:hasOffset |
0
|
| https://www.w3.org/2000/01/rdf-schema#label |
OEIS:A000124
|
| gptkbp:bfsParent |
gptkb:Erdős–Szekeres_numbers
|
| gptkbp:bfsLayer |
5
|