Sequences

First gap of n in sequence A038593 (lower terms).

First gap of n in sequence A038593 (upper terms).

[ n/F_2 ] + [ n/F_3 ] + [ n/F_4 ] +..., F_n=Fibonacci numbers.

a(n)-th and (a(n)+1)-st primes are the first pair of primes that differ by exactly 2n; a(n) = -1 if no such pair of primes exists.

Convolution of A007054 (super ballot numbers) with A000984 (central binomial coefficients).

Minimum area rectangle into which squares of sizes 1, 2, 3, ... n can be packed.

Minimal value of |product(A) - product(B)| where A and B are a partition of {1,2,3,...,n}.

a(n)=[ n/3 ] + [ n/4 ] + [ n/7 ] + [ n/11 ] + [ n/18 ] + [ n/29 ] + [ n/47 ] + [ n/76 ] + [ n/123 ] + [ n/199 ]... (using Lucas numbers A000204).

[ n/2 ]+[ n/3 ]+[ n/4 ]+[ n/7 ]+[ n/11 ]+[ n/18 ]+[ n/29 ]+[ n/47 ]+[ n/76 ]+[ n/123 ]+[ n/199 ]+... (using Lucas numbers A000032).

Concatenations of two squares in two ways.

Number of nonnegative solutions of x1^2 + x2^2 + ... + x5^2 = n.

Primes p such that the p-th Fibonacci number is composite.

Numbers that are not the difference between two positive cubes.

A finite series from the lyrics of La Farolera, a Latin American traditional children's song.

Triangle read by rows: T(n,k)=A(n,k)*binomial(n+k-1,n), where A(n,k) are the Eulerian numbers (A008292).

Fourth powers ending in a (different) positive fourth power.

Cubes ending in a (different) positive cube.

Squares ending in a different nonzero square.

Convolution of A007054 (Super ballot numbers) with A000302 (powers of 4).

Primes ending in a (different) prime.

Fifth powers ending nontrivially in a nonzero fifth power.

Sixth powers ending nontrivially in a nonzero sixth power.

Seventh powers ending nontrivially in a nonzero seventh power.

Eighth powers ending nontrivially in a nonzero eighth power.

Ninth powers ending nontrivially in a nonzero ninth power.

Tenth powers ending nontrivially in a nonzero tenth power.

Concatenate i >= 1 and j >= 1, then sort.

Squares that are the sum of the divisors of some number.

Duplicate of A030000.

a(n)^2 is smallest square containing the string 'n'.

Indices of primes at which the prime race 4k-1 vs. 4k+1 is tied.

Square numbers that are concatenations of two or more prime numbers.

Numbers whose concatenation of prime factors (with multiplicity) is a square.

Smallest odd number with n prime factors all of different number of decimal digits.

Smallest n-digit prime * smallest (n+1)-digit prime.

Nextprime(2^0)*nextprime(2^1)*nextprime(2^2)*...*nextprime(2^n).

Convolution of A000917 with A000984 (central binomial coefficients).

Excess of 4k-1 primes over 4k+1 primes, beginning with prime 2.

Riesel problem: Smallest prime of form n*2^m-1, m >= 0, or 0 if no such prime exists.

Smallest prime == -1 (mod n).

Prime powers q for which f(g(m(q))) = m(q), where f = A051703, g = A008475 and m = A003418.

a(n) = prime(n)^2 mod prime(n-1).

Primes p such that p^2 mod q is odd, where q is the previous prime.

Incrementally largest term in continued fraction for Champernowne constant (A030167).

Position of the incrementally largest term in continued fraction for Champernowne constant (A030167).

Position of the first occurrence of n in continued fraction for Champernowne constant (A030167).

a(n) = floor(n*(n+1/2)/2).

Primes of the form (k-th primorial) + (k+1)-st prime.

a(n) = floor(n*(n+1/2)/4).

a(n) is the smallest prime > product of the first n primes (A002110(n)).