70381

Properties

Appears in sequences

• a(n) is the index of the smallest triangular number containing exactly n 7's.at n=5A048362
• Sum of all terms on the two principal diagonals of a 2n+1 X 2n+1 square spiral.at n=23A114254
• Largest prime factor in A071576 starting from 4th position.at n=7A123248
• Primes p such that 2*p^4+-9 are also prime.at n=33A174365
• The smallest prime q > p = prime(n) such that p*(q-p)+q, p*(q-p)-q, q*(q-p)+p and q*(q-p)-p are simultaneously prime, or 0 if no such q exists.at n=36A180481
• Numbers k such that 63*10^k + 1 is prime.at n=27A271361
• Prime numbersat n=6975