Sequences

Number of binary sequences of length n with an even number of ones, at least two of the ones being contiguous.

Numbers k such that k^2+k+2 is a palindrome.

Palindromes of form k^2 + k + 2.

Numbers k such that k^2+k+3 is a palindrome.

Palindromes of form k^2 + k + 3.

Numbers k such that k^2 + k + 4 is a palindrome.

Palindromes of form k^2 + k + 4.

Numbers k such that k^2+k+5 is a palindrome.

Numbers k such that k^2 + 1 is a palindrome.

Palindromes of form k^2 + 1.

Palindromes of form k^2 + k + 6.

Numbers k such that k^2+k+7 is a palindrome.

Palindromes of form k^2 + k + 7.

Numbers k such that k^2+k+8 is a palindrome.

Palindromes of form k^2 + k + 8.

Numbers k such that k^2+k+9 is a palindrome.

Palindromes of form k^2 + k + 9.

Palindromes of form k^2 + k + 5.

Numbers k such that k^2+k+6 is a palindrome.

Number of independent subsets of nodes in graph formed from n-fold subdivision of tetrahedron.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 4-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 5-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 6-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 7-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 8-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 9-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 10-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 11-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of 12-dimensional simplex.

Number of independent subsets of nodes in graph formed from n-fold subdivision of triangle.

Number of primitive polynomials of degree n over GF(5).

a(n) = phi(4^n-1)/(2*n).

Number of primitive polynomials of degree n over GF(7).

Number of primitive polynomials of degree n over GF(8).

Number of primitive polynomials of degree n over GF(9).

Irregular triangle in which first row is 1, n-th row (n>1) gives prime factors of n with repetition.

a(n) = n^n^n^..^n (6-n terms, n<=5).

Irregular triangle in which first row is 1, n-th row (n > 1) lists distinct prime factors of n.

Take the list 1,2,3,4,... and replace each n with all d > 1 that divide n.

Triangle read by rows in which row n lists the divisors of n.

Irregular triangle read by rows in which row n lists the proper divisors of n (those divisors of n which are < n), with the first row {1} by convention.

Numbers k such that k^2 + k + 3 is prime.

Primes of form n^2 + n + 3.

Numbers k such that k^2 + k + 5 is prime.

Primes of the form k^2 + k + 5.

Numbers k such that k^2 + k + 7 is prime.

Numbers k such that k^2 + k + 9 is prime.

Primes of the form k^2 + k + 9.

Numerator of Sum_{p prime, p-1|n} 1/p.

Denominator of Sum_{p prime, p-1 divides n} 1/p.