77270

Appears in sequences

• Numbers k such that k-1, k-3, k-7 and k-9 are all prime.at n=31A064974
• Self-convolution square of A108447.at n=7A118341
• Triangle, read by rows, where diagonals are successive self-convolutions of A108447.at n=52A118343
• a(1)=2, a(2)=2, a(n)=a(n-2)+floor(a(n-2)*a(n-1)/(a(n-2)+a(n-1))).at n=50A173091
• Even numbers such that the sum of the odd divisors is a Fibonacci number F and the sum of the even divisors is 2F.at n=12A274062
• G.f.: exp( Sum_{n>=1} A322201(n)*x^n/n ), where A322201(n) is the coefficient of x^n*y^n/(2*n) in Sum_{n>=1} -log(1 - (x^n + y^n)).at n=10A322202