Calculator programs · Number and Algebra
Sequences: the least n with Sₙ > K
For an arithmetic or geometric sequence: the least n whose sum passes K, with that term and that sum.
Number and Algebra
When it helps
The least-n question is in every one of the last 14 years. By hand it means an inequality with logs or a quadratic; the program counts terms instead, and gives you a value to check your working against.
At each prompt
- a, the first term, r, what each term is multiplied by (1 for an arithmetic sequence), d, what is then added (0 for a geometric sequence), K, the sum to pass
- Size
- 56 bytes
- Keying in
- about 3–5 min to key in (111 presses)
- Run mode
- COMP
- Memories it overwrites
- A, B, C, D, X, Y, M