50051

Properties

Appears in sequences

• Primes which can be expressed as concatenation of powers of 5 and 0's.at n=23A066596
• Let p run through the primes; write p in base 10 and then interpret it in base 128 getting a number q; if q is prime then adjoin q to the sequence.at n=17A090718
• Primes of form n.0.n+1, where '.' represents concatenation. Or, primes of form 10^(k+1)*n + n + 1, where k is the number of digits in n.at n=7A096525
• Primes in carryless arithmetic mod 10 in which all digits except the rightmost are zero or five.at n=20A169984
• Base-6 pandigital primes: primes having at least one of each digit 0,1,2,3,4,5 when written in base 6.at n=2A175278
• Primes having only {0, 1, 5} as digits.at n=18A199325
• Primes formed by concatenating palindromes having even number of digits with 1.at n=17A210534
• Primes p with p + 2, prime(p) + 2 and prime(prime(p)) + 2 all prime.at n=10A236481
• Lesser of twin primes for which phi(p-1) < phi(p+1).at n=11A286715
• Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(0) + b(1) + ... + b(n-1), where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.at n=17A295053
• Lesser of twin primes p >= 5 for which phi(p+1)/phi(p-1) reaches record value, where phi(n) is the Euler totient function (A000010).at n=4A326356
• Expansion of e.g.f. T(x) satisfying T(x) = (1/2) * sinh( 2*x*cosh( x*sqrt(1 + 4*T(x)^2) ) ), where a(n) is the coefficient of x^(2*n+1)/(2*n+1)! in T(x) for n >= 0.at n=3A372814
• Primes having only {0, 1, 5, 8} as digits.at n=40A386033
• Prime numbersat n=5138