75843

Appears in sequences

• Odd pentagonal pyramidal numbers.at n=13A015223
• Numbers n such that n*phi(n-1) is a perfect square.at n=30A069069
• a(n) = (n+1)*(2n+1)^2.at n=26A139757
• Pentagonal pyramidal numbers divisible by 3.at n=35A299412
• Numbers k such that k![4] - 32 is prime, where k![4] = A007662(k) = quadruple factorial.at n=32A329167
• a(n) = number of chord labeled loopless diagrams by number of K_4.at n=3A348815
• Array read by antidiagonals: A(n,k) is the number of permutations of n copies of 1..k with values introduced in order and without cyclically adjacent elements equal.at n=24A369923