35569

Properties

Appears in sequences

• a(1) = 0, a(2) = -2; for n > 2, a(n) + a(n-2) - a(n-3) - a(n-5) - ... - a(n-p) = (-1)^(n+1)*n if n is prime, otherwise = 0, where p = largest prime < n.at n=55A002120
• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 25.at n=7A031613
• "DGK" (bracelet, element, unlabeled) transform of 1,3,5,7,...at n=14A032234
• Primes of form prime(1) + ... + prime(k) + 1.at n=17A053845
• Leading diagonal of triangle in A072467.at n=25A072468
• Out of all the n-digit primes, which one takes the longest time to appear in the digits of Pi (ignoring the initial 3)? The answer is a(n), and it appears at position A076130(n).at n=4A076106
• Lesser member p of cousin primes (p, p+4) such that (p+1, p+2, p+3) all have the same number of prime divisors (counted with multiplicity).at n=26A094230
• Primes that are a concatenation of 3, 5 and a prime.at n=25A101219
• Primes of the form 6*k^2 - 5.at n=22A201791
• Least integer m > 0 with pi(m*n) = sigma(m+n), where pi(.) and sigma(.) are given by A000720 and A000203.at n=30A247604
• Numbers k such that (56*10^k + 691)/9 is prime.at n=22A291866
• a(n) = p(n^2*p(n)), where p(x) is the least prime > x.at n=31A378137
• Prime numbersat n=3787