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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A255310 Positive integers not the sum of iterated binary logs.

Original entry on oeis.org

2, 5, 6, 11, 20, 21, 22, 39, 72, 137, 266, 267, 524, 1037, 2062, 4111, 8208, 16401, 32786, 65555, 65556, 65557, 65558, 131095, 262168, 524313, 1048602, 2097179, 4194332, 8388637, 16777246, 33554463, 67108896
Offset: 1

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Author

Paul Boddington, Feb 20 2015

Keywords

Examples

			Clearly A232779 is increasing, and A232779(n) equals 1 + A232779(n - 1) unless n is a power of 2. Therefore this sequence consists of all numbers strictly between A232779(2^r - 1) and A232779(2^r) for some r. For example, A232779(15) = 15 + 3 + 1 = 19, whereas A232779(16) = 16 + 4 + 2 + 1 = 23, so this sequence includes the terms 20, 21, 22.
The sequence can also be obtained using the sequence b(n) = A255309(n).
Suppose t >= 2 is a power of 2. Let s be the sum of b(r) for r from 1 to t - 1.
Then the numbers t + s (inclusive) to t + s + b(t) (exclusive) are in this sequence, and all terms can be obtained in this way.
For example, if t = 16, then s = b(1) + b(2) + ... + b(15) = 4, and b(16) = 3, so the bounds are 16 + 4 = 20 and 16 + 4 + 3 = 23, producing the terms 20, 21, 22.
		

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