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 1-5 of 5 results.

A095109 Sum of diving indices of all 4k+3 integers in range ]2^n,2^(n+1)].

Original entry on oeis.org

0, 0, 0, 3, 13, 40, 194, 389, 1407, 3646, 13300, 39166, 131464, 389575, 1627565, 5556317, 19913811, 72249861, 272188855, 996509475
Offset: 1

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Author

Antti Karttunen, Jun 01 2004

Keywords

Comments

Diving index is explained at A095269.

Crossrefs

Cf. A095110.

A095104 Diving index of the n-th 4k+3 prime (A002145(n)).

Original entry on oeis.org

0, 0, 0, 3, 0, 0, 3, 0, 0, 3, 0, 0, 0, 0, 7, 7, 0, 3, 0, 3, 0, 11, 0, 0, 3, 13, 61, 0, 0, 0, 0, 3, 3, 0, 3, 7, 0, 45, 3, 0, 0, 0, 0, 7, 7, 35, 0, 7, 35, 3, 0, 3, 3, 0, 3, 15, 0, 0, 3, 15, 3, 0, 0, 7, 3, 0, 45, 3, 0, 0, 3, 3, 7, 7, 0, 3, 0, 3, 0, 3, 0, 0, 7, 7, 0, 0, 0, 67, 0, 0, 3, 0
Offset: 1

Views

Author

Antti Karttunen, Jun 01 2004

Keywords

Comments

Diving index of an odd number n is the first integer u > 1 where Sum_{i=1..u} J(i/n) results -1 and zero if never. Here J(i/n) is Jacobi symbol of i and n, which reduces to a Legendre symbol L(i/n) when n is a prime.

Crossrefs

a(n)=A095105(n)+1 modulo A002145(n). Cf. A095106, A095108 (same sequence with zeros removed), A095269.

A095270 Length of maximal Motzkin path prefix in the Jacobi-vector of 4n+3.

Original entry on oeis.org

2, 6, 10, 14, 2, 22, 26, 30, 34, 38, 2, 46, 9, 54, 58, 62, 2, 70, 74, 78, 82, 86, 2, 94, 9, 102, 6, 110, 2, 118, 6, 6, 130, 134, 2, 142, 7, 150, 7, 158, 2, 166, 170, 174, 10, 182, 2, 190, 33, 198, 7, 18, 2, 214, 9, 12, 60, 230, 2, 238, 242, 6, 250, 254, 2, 262
Offset: 1

Views

Author

Antti Karttunen, Jun 01 2004

Keywords

Crossrefs

Formula

a(n) = A095269(n)-1 modulo A004767(n).

A095271 Diving index of A095101(n).

Original entry on oeis.org

3, 3, 10, 3, 3, 10, 7, 3, 7, 7, 3, 8, 8, 3, 11, 3, 34, 8, 19, 3, 10, 13, 61, 3, 7, 3, 7, 8, 3, 10, 3, 32, 7, 3, 58, 7, 3, 45, 3, 7, 3, 13, 31, 3, 8, 7, 3, 10, 7, 35, 3, 8, 7, 35, 3, 14, 8, 3, 13, 22, 3, 8, 3, 103, 7, 15, 3, 7, 40, 3, 7, 15, 55, 3, 113, 31, 3, 7, 13, 3, 118
Offset: 1

Views

Author

Antti Karttunen, Jun 01 2004

Keywords

Crossrefs

Formula

a(n) = A095269(A095275(n)). See comments at A095269.

A095361 Ratio A095110(n)/A000079(n-2) rounded down.

Original entry on oeis.org

2, 6, 12, 20, 37, 52, 106, 200, 369, 657, 1226, 2191, 4268, 8076, 15291, 28931, 55124, 105982, 202482, 391505
Offset: 1

Views

Author

Antti Karttunen, Jun 12 2004

Keywords

Comments

This is the average length of maximum Motzkin path prefix (i.e. non-diving portion) found in the "Jacobi-vectors" of all 4k+3 integers in range ]2^n,2^(n+1)]. See A095269-A095270.
The ratios before rounding are: 2, 6, 12, 20, 37.875, 52.9375, 106.28125, 200.25, 369.179687, 657.445312, 1226.675781, 2191.126953, 4268.283691, 8076.054443, 15291.317139, 28931.598755, 55124.513184, 105982.564758, 202482.488968, 391505.689705.

Crossrefs

A095362 gives the same ratios rounded to nearest integer. A095357 gives similar ratios computed only for 4k+3 primes.

Formula

a(1) = 2, a(n) = floor(A095110(n)/A000079(n-2)) for n > 1.
Showing 1-5 of 5 results.