72554

Appears in sequences

• Numbers k such that k^2 + k - 1 and k^2 + k + 1 are twin primes and (k + 1)*(k + 1) + k + 1 - 1 and (k + 1)*(k + 1) + k + 1 + 1 are also twin primes.at n=15A088498
• 30*a(n) is the gap between sexy prime triples in the n-th sexy prime triple triple whose initial term is 7.at n=22A090776
• Start with a(1) = 1, a(2) = 1, then a(n)*3^k = a(n+1) + a(n+2), with 3^k the smallest power of 3 (k>0) such that all terms a(n) are positive integers.at n=26A233525
• Number of nX7 0..1 arrays with every element unequal to 0, 1, 2 or 7 king-move adjacent elements, with upper left element zero.at n=8A304229