30013

Properties

Appears in sequences

• Primes of the form j^2 + (j+1)^2.at n=41A027862
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 92 ones.at n=30A031860
• Primes p such that the Fibonacci iterations starting with (1, p) lead to a "nine digits anagram".at n=3A034588
• Lucky numbers N (A000959) such that Fibonacci iterations starting with (1, N) lead to a "nine digits anagram".at n=2A034589
• a(n) = n-th primorial (A002110) minus next prime.at n=6A060882
• Primes starting and ending with 3.at n=33A062333
• Smallest prime divisor of (n-th primorial - (n+1)-st prime).at n=3A065314
• Largest prime divisor of n-th primorial - (n+1)-st prime.at n=3A065316
• Third row of Pascal-(1,5,1) array A081580.at n=41A081589
• Primes of the form (4*k + 3)^2 + (4*k + 2)^2 where k=0,1,2,3,...at n=12A087872
• Primes P such that P=k*p(n)#-p(n+1) is prime for least k. Here p(i)# denotes the i-th primorial and p(i) denotes the i-th prime.at n=5A090188
• Smaller of a pair (p,q) of primes with (p+q)/2=prime(n)# and q-p is minimal.at n=4A094710
• First occurrence where n# - p is a prime for primes p = 3,5,...at n=4A096649
• Primes of the form 8*n^2 + 4*n + 1.at n=21A102130
• Smallest prime in kx^3+x+3 is prime.at n=20A114367
• Where records occur in A117831.at n=20A118474
• Triangle read by rows: row n gives coefficients of increasing powers of x in the polynomial (-1)^n*p(n), where p(n) is defined as follows. Let f(n) = n*(n+1)/2, g(n) = f(n)+1; then p(-1) = 0, p(0) = 1 and for n >= 1, p(n) = (x - f(n))*p(n - 1) - g(n - 1)^2*p(n - 2).at n=22A135049
• Twin prime pairs p, p+2 such that p+(p+2)+1 and p*(p+2)+1 are both square.at n=25A166564
• Number of (n+3)X(n+3) binary arrays with every 4X4 subblock commuting with each horizontal and vertical neighbor 4X4 subblock.at n=9A188096
• Number of 0..2 arrays x(0..n+1) of n+2 elements without any interior element greater than both neighbors or less than both neighbors.at n=10A200865