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 1-6 of 6 results.

A382708 Number of triples (i,j,k), 1 <= i < j < k <= n such that A064413(i) < A064413(k) < A064413(j).

Original entry on oeis.org

0, 0, 0, 0, 4, 4, 4, 14, 20, 39, 39, 39, 59, 97, 97, 97, 134, 162, 177, 260, 260, 280, 300, 360, 360, 423, 525, 694, 694, 722, 817, 895, 1129, 1129, 1162, 1254, 1546, 1546, 1615, 1751, 1856, 1925, 2326, 2326, 2436, 2546, 2625, 2704, 2783, 3061, 3104, 3196, 3415, 3458, 3458, 3699, 4439, 4439, 4590, 4890, 5725, 5725, 5842
Offset: 1

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Author

N. J. A. Sloane, Apr 04 2025

Keywords

Comments

This is the number of occurrences of the pattern "132" in the first n terms of A064413.

Examples

			The first 5 terms of A064413 are 1, 2, 4, 6, 3, and at that point we can see four occurrences of the pattern "132", namely the triples 143, 163, 243, and 263, so a(5) = 4.
		

Crossrefs

A382703 Numbers k which appear "prematurely" in A064413, that is, k appears before the k-th term.

Original entry on oeis.org

4, 6, 9, 12, 10, 15, 18, 14, 21, 24, 20, 22, 33, 27, 30, 25, 35, 28, 39, 36, 32, 34, 51, 42, 38, 57, 45, 44, 46, 69, 48, 50, 52, 54, 56, 63, 60, 55, 65, 70, 58, 87, 66, 62, 93, 72, 68, 74, 111, 75, 78, 76, 80, 82, 123, 81, 84, 88, 86, 129, 90, 85, 95, 100, 92, 94, 141, 96, 98, 104, 102, 99, 105, 108, 106, 159, 114, 110, 112, 116
Offset: 1

Views

Author

N. J. A. Sloane, Apr 04 2025

Keywords

Comments

a(n) = A064413(A382702(n)).

Examples

			4 appears in A064413 at the third term, so 4 is a term.
		

Crossrefs

A382704 Indices k where b(k) < k, where b is the EKG sequence A064413.

Original entry on oeis.org

5, 10, 14, 17, 20, 27, 28, 33, 37, 43, 50, 57, 61, 67, 74, 78, 81, 89, 93, 100, 107, 115, 124, 128, 134, 138, 151, 160, 167, 171, 182, 189, 197, 203, 207, 210, 213, 216, 236, 253, 259, 264, 279, 287, 290, 297, 305, 314, 328, 336, 344, 363, 371, 377, 381, 401, 420, 430, 438, 444, 458, 462, 474, 487, 501, 510, 517, 530, 540, 549
Offset: 1

Views

Author

N. J. A. Sloane, Apr 04 2025

Keywords

Examples

			A064413(5) = 3 < 5, so 5 is a term.
		

Crossrefs

A382707 a(n) = number of indices k, 1 <= k <= n, such that A064413(k) < k.

Original entry on oeis.org

0, 0, 0, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 5, 5, 5, 5, 5, 6, 7, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 13, 13, 13, 13, 14, 14, 14, 14, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 17, 17, 17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 19
Offset: 1

Views

Author

N. J. A. Sloane, Apr 04 2025

Keywords

Crossrefs

A382705 Numbers k which are "delayed" in A064413, that is, k appears after the k-th term.

Original entry on oeis.org

3, 5, 7, 16, 11, 26, 13, 17, 19, 23, 49, 29, 31, 37, 41, 77, 43, 47, 91, 53, 59, 61, 121, 67, 71, 73, 79, 83, 89, 169, 97, 101, 103, 107, 109, 205, 209, 113, 127, 131, 137, 139, 149, 151, 289, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283, 293, 307, 311
Offset: 1

Views

Author

N. J. A. Sloane, Apr 04 2025

Keywords

Comments

a(n) = A064413(A382704(n)).

Examples

			3 only appears in A064413 at the fourth term, so 3 is a term.
		

Crossrefs

A382706 a(n) = number of indices k, 1 <= k <= n, such that A064413(k) > k.

Original entry on oeis.org

0, 0, 1, 2, 2, 3, 4, 4, 5, 5, 6, 7, 8, 8, 9, 10, 10, 11, 12, 12, 13, 14, 15, 16, 17, 18, 18, 18, 19, 20, 21, 22, 22, 23, 24, 25, 25, 26, 27, 27, 28, 29, 29, 30, 31, 32, 33, 34, 35, 35, 36, 37, 38, 39, 40, 41, 41, 42, 43, 44, 44, 45, 46, 46, 47, 48, 48, 49, 50, 51, 52, 53, 54, 54, 55, 56, 57, 57, 58, 59, 59, 60, 61, 62, 63, 64, 65, 66
Offset: 1

Views

Author

N. J. A. Sloane, Apr 04 2025

Keywords

Crossrefs

Showing 1-6 of 6 results.