$A$ person wants to climb a $n$-step staircase using one step or two steps at a time. Let $C_n$ denote the number of ways of climbing the $n$-step staircase. Then $C_{18} + C_{19}$ equals

  • A
    $C_{20}$
  • B
    $C_{21}$
  • C
    greater than $C_{21}$
  • D
    less than $C_{20}$

Explore More

Similar Questions

What is the sum of $n$ terms of the series $2 + 5 + 14 + 41 + \dots$?

Difficult
View Solution

The value of $1^3 - 2^3 + 3^3 - \dots + 15^3$ is:

The value of $(0.05)^{\log_{\sqrt{20}}(0.1 + 0.01 + 0.001 + \dots)}$ is

Difficult
View Solution

The sum of $n$ terms of the series $1^{3}+3^{3}+5^{3}+7^{3}+\ldots$ is

$5^{2}+6^{2}+7^{2}+\ldots+20^{2} =$

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo