A, B, C and D are triangular numbers.
A, B and C are always consecutive while D is their sum.
Determine (and explain as best as possible1) how such sets of values are distributed across the number system.
1. This can be explained in terms of a single variable expression.
The ordinal number x of a triangular number Tx
which is the sum of three consecutive triangular numbers can be found where
x = SQRT(3n2
+ 9n + 33/4) - (1/2)
such that x is an integer and n is the ordinal number Tn
of the first of the three consecutive triangular numbers.
Posted by Dej Mar
on 2009-11-30 04:40:05