cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A256470 a(n) = A256469(n) - A256468(n).

Original entry on oeis.org

0, 1, 2, 3, 1, 6, 1, 3, 3, 0, 3, 2, -2, 0, 4, 6, 0, 4, 4, 0, 2, 3, 10, 13, -1, -2, 3, 4, 4, 34, 5, 3, 5, 17, 6, 2, 8, -2, -6, 3, -4, -4, -3, -2, -1, 9, 25, -2, -6, -4, 12, 4, 6, 9, -6, 18, 1, -2, -11, 7, -8, 27, -10, 3, -1, 12, 11, 13, -3, 5, 3, 5, -13, -8, 10, 16, -4, 14, 3, 12, -3, 23, 5, 4, 6, -8, 19, -13, 1, 0
Offset: 1

Views

Author

Antti Karttunen, Mar 30 2015

Keywords

Comments

a(n) = Difference between the number of primes occurring in range [prime(n)*prime(n+1), prime(n+1)^2] and the number of primes occurring in range [prime(n)^2, prime(n)*prime(n+1)].
In other words, a(n) tells how many more primes there are in the latter part of the range prime(n)^2 .. prime(n+1)^2 (after the geometric mean of its limits), than in its first part (before the geometric mean of its limits).

Crossrefs

Positions of zeros: A256471. Cf. also A256472, A256473.
Positions of nonnegative terms: A256474, negative terms: A256475.
Positions of strictly positive terms: A256476, terms less than or equal to zero: A256477.

Programs

Formula

a(n) = A256469(n) - A256468(n).
a(n) = 3 - A256449(n).

A256475 Numbers n for which there are more primes in range [prime(n)^2, prime(n)*prime(n+1)] than in range [prime(n)*prime(n+1), prime(n+1)^2].

Original entry on oeis.org

13, 25, 26, 38, 39, 41, 42, 43, 44, 45, 48, 49, 50, 55, 58, 59, 61, 63, 65, 69, 73, 74, 77, 81, 86, 88, 92, 96, 98, 101, 103, 106, 107, 108, 109, 116, 117, 120, 121, 122, 124, 125, 128, 141, 142, 143, 145, 146, 148, 149, 151, 155, 158, 159, 166, 169, 172, 173, 177, 179, 181, 182, 183, 190, 191, 194, 195, 196, 197, 206
Offset: 1

Views

Author

Antti Karttunen, Mar 30 2015

Keywords

Comments

Positions of negative terms in A256470.
Equally: Numbers n for which there are less primes in range [prime(n)*prime(n+1), prime(n+1)^2] than in range [prime(n)^2, prime(n)*prime(n+1)].

Crossrefs

Complement: A256474.
Setwise difference of A256477 and A256471.
Cf. A256485 (corresponding primes).
Cf. A256470.

Programs

A256476 Numbers n for which there are more primes in range [prime(n)*prime(n+1), prime(n+1)^2] than in range [prime(n)^2, prime(n)*prime(n+1)].

Original entry on oeis.org

2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 15, 16, 18, 19, 21, 22, 23, 24, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 40, 46, 47, 51, 52, 53, 54, 56, 57, 60, 62, 64, 66, 67, 68, 70, 71, 72, 75, 76, 78, 79, 80, 82, 83, 84, 85, 87, 89, 91, 93, 94, 95, 97, 99, 100, 102, 104, 105, 111, 112, 113, 114, 115, 118, 119, 123
Offset: 1

Views

Author

Antti Karttunen, Mar 30 2015

Keywords

Comments

Positions where A256470 is strictly positive.

Crossrefs

Complement: A256477.
Setwise difference of A256474 and A256471.
Cf. A256470.

Programs

Showing 1-3 of 3 results.