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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A324156 Irregular triangle T(n,k) read by rows in which row n lists the numbers m such that the number of prime numbers <= m is equal to the number of base-n zerofree numbers <= m.

Original entry on oeis.org

2, 3, 4, 3, 113, 114, 115, 116, 117, 118, 119, 120, 199, 200, 201, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 482, 483, 491, 492, 493, 494, 495, 496, 497, 498, 344251, 344252, 344253, 344254, 344255, 344256, 351902, 353501, 353502, 353503
Offset: 2

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Author

Hieronymus Fischer, Jul 16 2019

Keywords

Comments

The offset is 2 since the least base (= row) for which the definition makes sense is n = 2.
The least term of row n is T(n,1) = A324154(n). The last term of row n is T(n,j) = A324155(n), where j = A324157(n) is the number of terms of the n-th row.
Terms of rows higher than 5 are unknown, but they are bounded by the above rule. For example, the first term of the 6th row is T(6,1) = A324154(n) = 4.1645*10^15, approximately. The last term of the 6th row is A324155(n) = 1.46705*10^16, approximately.

Examples

			T(2,1) = 2, since pi(2) = 1 = numOfZerofreeNum_2(2) where numOfZerofreeNum_n(k) = number of base-n zerofree numbers <= k.
T(2,2) = 3, since pi(3) = 2 = numOfZerofreeNum_2(3).
T(3,2) = 4, since pi(4) = 2 = numOfZerofreeNum_2(3).
T(3,1) = 3, since pi(3) = 2 = numOfZerofreeNum_3(3).
T(3,2) = 113, since pi(113) = 30 = numOfZerofreeNum_3(113).
Triangle T(n,k) begins:
2, 3, 4;
3, 113, 114, 115, 116, 117, 118, 119, 120, 199, 200, 201, 293, 294, 295, 296, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 482, 483, 491, 492, 493, 494, 495, 496, 497, 498;
344251, 344252, 344253, 344254, 344255, 344256, 351902, 353501, 353502, 353503, 353504, 353505, 353506, 353507, 353508, 353509, 353510, 353511, 353512, 353513, 353514, 353515, 353516, 353517, 353518, 353519, 353520, 353521, 353522, 353523, 353524, 353525, 353526, 353631, 353632, 353633, 353634, 353635, 353636, 601379, 601380, 601381, 601382, 601383, 601384, 601385, 601386, 601387, 601388, 601389, 601390, 601391, 601392, 601393, 601394, 601395, 601396, 617903, 617904, 617905, 617906, 617907, 617908, 867281, 867282, 867283, 867284, 867285, 867286, 867287, 867288, 867289, 867290, 867291, 867292, 867293, 867294, 867295, 867296, 867297, 867298, 867299, 867300, 876414, 876431, 876432, 876437, 877213, 877214, 877215, 877216, 877217, 877218, 877219, 877220, 877221, 877222, 878014, 878021, 878022, 878037, 1139549, 1139550, 1139551, 1139552, 1139553, 1139554, 1139555, 1139556;
33182655683, 33182655684, 33182655685, 33182655686, 33182655687, 33182655688;
		

Crossrefs

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