18127

Properties

Appears in sequences

• Number of n-node unrooted steric quartic trees; number of n-carbon alkanes C(n)H(2n+2) taking stereoisomers into account.at n=15A000628
• Largest prime == 7 (mod 8) with class number 2n+1.at n=19A002147
• a(0) = 1, a(n) = 29*n^2 + 2 for n>0.at n=25A010019
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 74 ones.at n=19A031842
• Denominators of continued fraction convergents to sqrt(329).at n=10A041621
• Numbers n such that n and n+4^k are all primes for k=1,2,3.at n=36A049493
• Primes at which the difference pattern X42Y (X and Y >= 6) occurs in A001223.at n=33A052164
• Primes p such that x^53 = 2 has no solution mod p.at n=36A059258
• Primes p such that x^18 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=35A059664
• Primes p such that x^54 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=37A059665
• Primes p such that x^36 = 2 has no solution mod p, but x^12 = 2 has a solution mod p.at n=24A059668
• Number of unrooted steric quartic trees with n (unlabeled) nodes and possessing a centroid; number of n carbon alkanes C(n)H(2n +2) with a centroid when stereoisomers are regarded as different.at n=14A086194
• Primes p such that there exist three primes q, r and s with p^3=q^3+r^3+s^3.at n=27A114923
• a(n) is the least prime for which the n-th term of the sequence S(a(n)) belongs to A007500, where each term of S(p) is the least prime >= the reversal of the previous term.at n=14A135436
• Primes p such that the left prime neighbors p1, p2 of p as well as the right prime neighbors q1, q2 of p form twin prime pairs and the sum p1 + p2 + p + q1 + q2 is also prime.at n=19A138396
• Primes congruent to 14 mod 59.at n=38A142741
• Primes congruent to 10 mod 61.at n=36A142808
• Number of ways to place zero or more nonadjacent 1,1 2,1 3,0 3,1 4,2 4,3 4,4 5,2 polyhexes in any orientation on a planar nXnXn triangular grid.at n=8A155392
• Primes of the form x^5-y^4, where x,y >= 1.at n=6A161747
• Table with T(n,k) the number of word structures of length n which can be decomposed into k palindromes but not fewer.at n=52A188792