Consecutive Integers Calculator Sum of n consecutive integers. Start at Count Sum 55 Step-by-step with your numbers: 1. Values used: 2. Start at = 1 3. Count = 10 4. Sum = 55 Did we solve your problem today? 👍 Yes 👎 No Thanks for the feedback! Sum = n(2a + n − 1)÷2. FAQ 1 to n? n(n+1)/2. Related calculators Triangular Number Calculator Find the nth triangular number. Arithmetic Sequence Calculator Find the nth term and sum of an arithmetic sequence. Digit Sum Calculator Add up the digits of a number.