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.

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A129602 In the binary expansion of n replace each run of k 0's (or 1's) with 2k-1 0's (or 1's), except in the most significant run where we double the number of 0's (or 1's).

Original entry on oeis.org

0, 3, 6, 15, 24, 13, 30, 63, 96, 49, 26, 55, 120, 61, 126, 255, 384, 193, 98, 199, 104, 53, 110, 223, 480, 241, 122, 247, 504, 253, 510, 1023, 1536, 769, 386, 775, 392, 197, 398, 799, 416, 209, 106, 215, 440, 221, 446, 895, 1920, 961, 482, 967, 488, 245, 494
Offset: 0

Views

Author

Antti Karttunen, May 01 2007

Keywords

Examples

			a(1) = 3, as 1 is 1 in binary and doubling the number of 1's (in the only run) gives binary 11, 3 in decimal. a(9) = 49, as 9 is 1001 in binary and replacing the most significant run '1' with '11' and the center run '00' with '000' and the least significant run '1' with '1', we get 110001 in binary, 49 in decimal.
		

Crossrefs

Central diagonal of array A129600, a(n) = A129600bi(n, n). Cf. A129594. For n > 0, a(n) = A004760(A129603(n)+1).

Extensions

Edited definition. - N. J. A. Sloane, Dec 20 2023

A129601 Table T(i,j): T(0,0), T(1,0), T(1,1), T(2,0), T(2,1), T(2,2), ... of binary runlength encoded product of i and j.

Original entry on oeis.org

0, 1, 3, 2, 4, 6, 3, 7, 8, 15, 4, 8, 12, 16, 24, 5, 11, 9, 23, 19, 13, 6, 12, 14, 24, 28, 17, 30, 7, 15, 16, 31, 32, 47, 48, 63, 8, 16, 24, 32, 48, 39, 56, 64, 96, 9, 19, 17, 39, 35, 25, 33, 79, 71, 49, 10, 20, 22, 40, 44, 18, 46, 80, 88, 38, 26, 11, 23, 19, 47, 39, 27, 35, 95
Offset: 0

Views

Author

Antti Karttunen, May 01 2007

Keywords

Comments

This is the upper triangular region of array A129600 (or equally, the lower triangular region, because A129600 is symmetric).
Showing 1-2 of 2 results.