19777

Properties

Appears in sequences

• a(1) = 1; thereafter a(n+1) = floor(sqrt(2*a(n)*(a(n)+1))).at n=27A001521
• Expansion of e.g.f. cos(sin(x)/cosh(x)), even powers only.at n=4A009051
• Expansion of e.g.f.: exp(sinh(x)/cos(x)).at n=8A009234
• Dot product of (1,2,...,n) and first n distinct Fibonacci numbers.at n=13A094584
• Concatenation of the terms of the n-th row in A096135, divided by n.at n=3A096136
• Primes of the form 128n+65.at n=36A105129
• Primes with digit sum = 31.at n=31A106767
• Primes p such that p's set of distinct digits is {1,7,9}.at n=19A108384
• Numbers k such that k and k^2 use only the digits 1, 2, 3, 7 and 9.at n=19A136983
• Primes congruent to 12 mod 59.at n=39A142739
• Primes p such that (p-1)*p*(p+1)-p+2 and (p-1)*p*(p+1)+p-2 are primes.at n=28A154944
• Primes p such that both pi(p) and the concatenation of pi(p) and p are prime, where pi is the prime counting function.at n=33A155032
• Starting at a(1)=2, a(n) is the smallest prime larger than a(n-1) such that the sum of odd digits of a(n) is not smaller than the sum of odd digits of a(n-1).at n=38A158085
• Primes containing 777 as a substring.at n=3A167282
• a(n) = the smallest prime > (1/EulerGamma)^n.at n=17A172527
• a(n) = A175369(n^3).at n=7A175371
• Primes of the form 9n^3+4.at n=2A201265
• Primes p of the form penta(n)-3, where penta(n) is the n-th pentagonal number.at n=27A232537
• Least prime of the form x^2+13*n^2.at n=38A248409
• Primes p such that 2*p + 47 is a square.at n=41A269788