690900

Appears in sequences

• Consider 2n tennis players; a(n) is the number of matches needed to let every possible pair play each other.at n=23A062346
• Triangular numbers using only the curved digits 0, 3, 6, 8 and 9.at n=26A079653
• Triangular numbers composed of digits {0,6,9}.at n=8A119091
• The first of three consecutive hexagonal numbers the sum of which is equal to the sum of three consecutive primes.at n=24A298272