26317

Properties

Appears in sequences

• Largest prime factor of 2^n + 1.at n=34A002587
• a(n+1) is the smallest prime ending with a(n), where a(1)=7.at n=4A053584
• Numbers p from A001125 such that 2*p-3 is prime.at n=34A063939
• Composite-then-prime recurrence; a(2n) = a(2n-1)-th composite and a(2n+1) = a(2n)-th prime and a(1) = 1.at n=10A064961
• a(1) = 7; thereafter a(n) = the smallest prime of the form d0...0a(n-1), where d is a single digit, or 0 if no such prime exists.at n=4A077715
• Primes arising in A089562.at n=4A089563
• Primes arising in A089570.at n=3A089571
• Primes of the form prime(nk) followed by prime(k).at n=6A089788
• Primes of the form (k+1)*prime(k) + k*prime(k+1).at n=20A097241
• Primes of the form (prime(prime(k)) + prime(prime(k+1)))/2.at n=23A098042
• A006530(x)=2 is a local minimum if x=2^n. Running upward with argument x, the largest prime divisor should increase. The value of first peak is a(n).at n=33A102643
• Primes whose logarithms are known to possess binary BBP formulas.at n=33A104885
• Triangle read by rows: T(n,k) is the number of hill-free Dyck paths of semilength n and having k peaks at level 2; 0<= k<=n-1, n>=2 (a Dyck path is said to be hill-free if it has no peaks at level 1).at n=66A114626
• Primes p such that their cubes are pandigital.at n=26A124629
• Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n and having k UDUD's starting at level 0; here U=(1,1), D=(1,-1) (0<=k<=n-1).at n=68A127153
• Sum of digits of n-th even perfect number.at n=20A138828
• Primes the squares of which are Fibbinary numbers (A003714).at n=34A144759
• Primes of the form 10n^2+6n+1.at n=20A154409
• Number of binary strings of length n with no substrings equal to 0001 0010 or 1011.at n=18A164450
• Numbers with d digits (d>0) which have at least 2d distinct primes as substrings.at n=29A168167