116025

Appears in sequences

• a(n) = (4*n+9)(!^4)/9(!^4), related to A007696(n+1) ((4*n+1)(!^4) quartic, or 4-factorials).at n=4A051621
• a(n) = 5*a(n-2) + 2*a(n-3).at n=16A135138
• a(n) is the least positive integer k such that 2^n-1 and k^n-1 are relatively prime.at n=47A260119
• a(n) is the smallest k > n such that psi(k) is the arithmetic mean of psi(k - n) and psi(k + n), or 0 if no such k exists.at n=32A292307
• Numbers that are product of a second hexagonal number (A014105) and a square pyramidal numbers (A000330) in at least two ways.at n=17A306122
• a(n) = A351477(n) * FB where F is the Fermat point of a primitive integer-sided triangle ABC with A < B < C < 2*Pi/3 and FA + FB + FC = A336329(n).at n=12A351802
• Number of invertible n X n Hankel matrices with entries in {0,1}.at n=8A391693