102378

Appears in sequences

• Smallest triangular number that contains the string n in its exact center.at n=23A062690
• The smallest triangular number that contains the digits of n in its exact middle.at n=22A163598
• Numbers with exactly six distinct base-10 digits.at n=18A220076
• Triangular numbers which have one or more occurrences of exactly six different digits.at n=0A241789
• Triangular numbers n such that sigma(n) is a square number.at n=13A256151
• a(n) is the first triangular number whose decimal representation uses n distinct digits.at n=5A260214
• Triangular numbers k such that psi(k) is a square, where psi(k) is the Dedekind psi function (A001615).at n=30A292064