Sequences

Triangle of numbers arising from Gilbreath's conjecture: successive absolute differences of primes (read by antidiagonals upwards, omitting the initial row of primes).

Array of numbers read by upward antidiagonals, arising from Gilbreath's conjecture: leading row lists the primes; the following rows give absolute values of differences of previous row.

Second differences of primes.

Third differences of primes.

4th differences of primes.

5th differences of primes.

6th differences of primes.

7th differences of primes.

8th differences of primes.

9th differences of primes.

10th differences of primes.

Absolute values of differences of absolute values of second differences of primes.

Absolute values of differences of A036272.

Absolute values of differences of A036273.

The periodic part of the decimal expansion of 1/n. Any initial 0's are to be placed at end of cycle.

a(n) = A001864(n+1)/2.

Position of first term > 2 in n-th row of Gilbreath array shown in A036262.

Denominators in Taylor series for cot x.

Denominators in the Taylor series for tan(x).

Numerators in Taylor series for x * cosec(x).

Denominators in Taylor series for x * cosec(x).

Write cosec x = 1/x + Sum_{n>=1} e_n * x^(2n-1)/(2n-1)!; sequence gives numerators of e_n.

Write cosec x = 1/x + Sum e_n x^(2n-1)/(2n-1)!; sequence gives denominators of e_n.

Periodic vertical binary vectors of Fibonacci numbers.

Sequence A036284 written in octal.

Periodic vertical binary vectors of Fibonacci numbers, topmost bits being most significant.

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

a(n) = 1 + integer log of n: if the prime factorization of n is n = Product (p_j^k_j) then a(n) = 1 + Sum (p_j * k_j) (cf. A001414).

a(n) = n*2^n.

a(n) = n*3^n.

a(n) = n*5^n.

a(n) = n*6^n.

a(n) = n*7^n.

a(n) = n*8^n.

Numerator of Sum_{i=1..n} i/2^i.

Denominator of Sum_{i=1..n} i/2^i.

Number of Hadamard matrices of order n.

(n!)!, n>0 (note that A000197 is the correct version of this sequence, with a(0) = 1, not 0).

Binary Fibonacci (or rabbit) sequence.

Number of binary abstract 2-D configurations.

Numbers whose sum of even digits and sum of odd digits are equal.

Composite numbers k such that the digits of the prime factors of k are either 1 or 2.

Composite numbers whose prime factors contain no digits other than 1 and 3.

Composite numbers whose prime factors contain no digits other than 1 and 4.

Composite numbers whose prime factors contain no digits other than 1 and 5.

Composite numbers whose prime factors contain no digits other than 1 and 6.

Composite numbers whose prime factors contain no digits other than 1 and 7.

Composite numbers whose prime factors contain no digits other than 1 and 8.

Composite numbers whose prime factors contain no digits other than 1 and 9.

Composite numbers whose prime factors contain no digits other than 2 and 3.