28517

Properties

Appears in sequences

• Crystal ball sequence for squashed {D_5}^* lattice, perhaps the smallest example of a "non-superficial" lattice.at n=8A010025
• Numbers k such that the continued fraction for sqrt(k) has period 71.at n=28A020410
• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 10.at n=37A031423
• Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 23.at n=33A051964
• a(n) = ((6*n + 10)/27)*2^(n-1) + ((-1)^(n-1))*(6*n + 5)/27.at n=13A127976
• Primes of the form 3*k^2 + 9*k + 5.at n=35A171838
• Integers k such that 2^(k-1) == 1 (mod k) and 2^(m-1) == 1 (mod m), where m = k*(A000265(k-1) - 1) + 1 and A000265 gives the odd part of its argument.at n=17A187849
• Primes from merging of 5 successive digits in decimal expansion of sqrt(2).at n=27A198165
• Number of 3 X n 0..2 arrays with horizontal differences mod 3 never 1, vertical differences mod 3 never -1, and rows and columns lexicographically nondecreasing.at n=43A229446
• Molien series for invariants of finite Coxeter group A_10.at n=60A266779
• Primes p such that q=p^2+p+1 is prime and (q^2+q+1)/3 is prime.at n=34A322748
• Primes p such that 14*p + 1 divides 2^p - 1.at n=25A350702
• Prime numbersat n=3102