124251

Appears in sequences

• Smallest triangular number that contains the string n in its exact center.at n=42A062690
• The smallest triangular number that contains the digits of n in its exact middle.at n=41A163598
• a(n) = m*(m+1)/2, where m = floor(n^(5/2)).at n=11A185542
• Triangular numbers composed of only digits with line segments or both line segments and curves {1, 2, 4, 5, 7}.at n=26A247021
• The first of three consecutive triangular numbers the sum of which is equal to the sum of three consecutive primes.at n=35A298168
• a(n) = Sum_{k=0..n} k! * k^(n-k).at n=8A367011