10680265

Appears in sequences

• a(n) is the smallest n-gonal pyramidal number greater than 1 which is also n-gonal; a(n) = 0 when one does not exist.at n=20A308488
• a(n) = (3*n^2 - 1) * (3*n^2 - 2) * (3*n^3 - 3*n + 1)/2.at n=7A344410
• a(n) is the smallest n-gonal number that is a Fermat pseudoprime to base 2 (A001567), or -1 if no such number exists.at n=20A371759
• Numbers that are simultaneously k-gonal and k-gonal pyramidal for some k >= 3.at n=22A373711