128879

Properties

Appears in sequences

• Smallest number that takes n steps to reach 0 under "k->min product of 2 numbers whose concatenation is k".at n=13A035933
• Numerators of continued fraction convergents to sqrt(357).at n=7A041676
• Primes of form p^2 - 2, where p is prime.at n=28A049002
• Primes p of form q^k-2 where q is also a prime and k > 1.at n=38A053705
• Special safe primes (from A005385) such that the next prime is also a safe prime.at n=19A059394
• A Chebyshev T-sequence with Diophantine property.at n=4A078369
• Number of n X n binary arrays with all ones connected only in a 11110-01111 pattern in any orientation.at n=8A147505
• Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 11110-01111 pattern in any orientation.at n=18A147507
• Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 11110-01111 pattern in any orientation.at n=19A147507
• Primes of the form p^q - q, where p and q are primes.at n=30A182474
• Emirps whose binary conversion remains emirp when read in decimal.at n=31A226972
• Smaller of Fermi-Dirac twin primes (A229064) which are not the smaller of twin primes (A001359).at n=34A229500
• a(n) = n^4 + 8*n^3 + 20*n^2 + 16*n + 2.at n=17A304725
• Numbers k such that tau(k) and tau(k+2) are both prime, where tau is the number of divisors function (the lesser of twin prime pairs are excluded).at n=36A343495
• Emirps that can be written as p*q+p+q where p and q are emirps.at n=34A352249
• List of connected graphs that are squares, encoded as in A076184.at n=34A382194
• Primes of the form p^q - 2, where p and q are primes.at n=32A389431
• Prime numbersat n=12064