129795

Appears in sequences

• Triangular numbers whose sum of aliquot divisors is also a triangular number.at n=12A083675
• a(n) = 1*3*5 + 3*5*7 + 5*7*9 + ... (n terms).at n=15A196506
• Triangular numbers T from A000217 such that (4*T+1)/13 is prime.at n=27A208294
• Triangular numbers such that the binary representation is of the form either Tbt or Tt, where T and t are binary representations of triangular numbers with equal binary length, and b is a binary digit: b = 1 or 0.at n=10A226736