Sequences

Sum of n consecutive primes starting at a(n) is prime (or 0 if impossible).

a(n) = n! + 2^n.

a(n+1) = a(n) + digital root (A010888) of a(n).

a(n) = (8^n + 2*(-1)^n)/3.

All values attained by the phi(n) function, in ascending order.

Primes with unique period length (the periods are given in A007498).

Palindromic reflectable primes.

Values not in range of Euler phi function.

a(n) = a(n-1) + sum of digits of a(n-1), a(1) = 5.

Wilson quotients: ((p-1)! + 1)/p where p is the n-th prime.

Numbers m such that every k <= m is a sum of proper divisors of m (for m>1).

Impractical numbers: even abundant numbers (A173490) that are not practical(2) (A007620).

Consider Leibniz's harmonic triangle (A003506) and look at the non-boundary terms. Sequence gives numbers appearing in denominators, sorted.

Integers written in factorial base.

Numbers m such that the product of proper divisors of m = m^k, k>1.

Number of M-sequences from multicomplexes on at most 6 variables with no monomial of degree more than n-1.

Sum of divisors of superabundant numbers (A004394).

Primitive modest numbers.

Reflectable emirps.

Repfigit (REPetitive FIbonacci-like diGIT) numbers (or Keith numbers).

Duplicate of A002562.

Number of solutions to non-attacking reflecting queens problem.

Numbers that are palindromic in bases 2 and 10.

Palindromic in bases 3 and 10.

Numbers k such that k^2 + k + 41 is composite.

Primes of form n^2 + n + 17.

Numbers k such that k^2 + k + 17 is composite.

Primes of form 3*k^2 - 3*k + 23.

Numbers k such that 3*k^2 - 3*k + 23 is composite.

Primes of form 2n^2 - 2n + 19.

Numbers k such that 2*k^2 - 2*k + 19 is composite.

Primes of the form 2*k^2 + 29.

Numbers k such that 2*k^2 +29 is composite.

Primes not of form | 3^x - 2^y |.

Primes not of form | 3^a +- 2^b | where a, b are nonnegative integers.

Generalized cuban primes: primes of the form x^2 + xy + y^2; or primes of the form x^2 + 3*y^2; or primes == 0 or 1 (mod 3).

Numbers k such that k*4^k + 1 is prime.

Numbers k such that k*10^k + 1 is prime.

Numbers k such that k*18^k + 1 is prime.

Number of set-like molecular species of degree n.

Number of set-like atomic species of degree n.

Describe the previous term! (method B - initial term is 1).

Final digit of prime(n).

Coefficients of L-series for elliptic curve "37a1": y^2 + y = x^3 - x.

Numbers k such that the standard deviation of 1,...,k is an integer.

Standard deviation of A007654.

Mass number of the most abundant isotope of the element with atomic number Z = n.

Maximal coefficient in (x + x^2 + x^4 + x^8 + ...)^n.

Numbers k such that (3^k + 1)/4 is prime.

Primes p such that Ramanujan number tau(p) is divisible by p.