30091

Properties

Appears in sequences

• Primes that remain prime through 3 iterations of function f(x) = 6x + 1.at n=21A023287
• Initial prime in set of 4 consecutive primes with common difference 6.at n=17A033451
• First term of balanced prime quartets: p(m+1)-p(m) = p(m+2)-p(m+1) = p(m+3)-p(m+2).at n=17A054800
• Primes with 21 as smallest positive primitive root.at n=5A061333
• Prime(n) and prime(n+3) use the same digits.at n=34A069795
• Primes for which the smallest positive primitive root is odd and nonprime.at n=13A070269
• Integer part of the geometric mean of all the distinct numbers formed by permuting the digits of concatenation of numbers from 1 to n.at n=4A078265
• Primes p such that the differences between the 5 consecutive primes starting with p are (6,6,6,4).at n=3A078969
• Primes p such that p, p+6, p+12, p+18 are consecutive primes and p = 6*k+1 for some k.at n=7A090837
• Expansion of x^2*(1+3*x+x^2-x^3+28*x^4+80*x^5)/(1-10*x^2+29*x^4-24*x^6).at n=11A122023
• a(n) is the smallest odd number that makes a(n)*2^N(n)-1 prime, where N(n) is the n-th Mersenne number that makes 2^N(n)-1 prime.at n=28A135434
• Primes p of the form : p+p^2+p^3-+4=prime.at n=11A154822
• Hypercomma numbers: n occurs in the sequence S[k+1]=S[k]+10*last_digit(S[k-1])+first_digit(S[k]) for each "legal" splitting n=concat(S[0],S[1]).at n=43A166508
• Primes p of the form 4m+3 for which there are exactly as many primitive roots modulo p in the interval [0,p/2] as in the interval [p/2,p].at n=27A172490
• a(n) = 2*a(n-1)+3*a(n-2)+5^n for n>1, a(0)=-2, a(1)=1.at n=6A200859
• Primes p = 1 mod 6 such that all three iterations p=(6p+1) give primes = 1 mod 6.at n=9A210686
• Primes p such that four consecutive primes starting with p are congruent to {1,2,3,4} (mod 5).at n=38A215607
• Smallest of four primes in arithmetic progression with common difference 6 and digit sum prime.at n=2A253216
• Least prime p such that pi(p*n) = pi(q*n)^2 for some prime q, where pi(x) denotes the number of primes not exceeding x.at n=27A260140
• Expansion of Product_{k>=1} 1/(1 - x^(2*k+1))^k.at n=45A263150