A020858 Decimal expansion of log_2(5).

2, 3, 2, 1, 9, 2, 8, 0, 9, 4, 8, 8, 7, 3, 6, 2, 3, 4, 7, 8, 7, 0, 3, 1, 9, 4, 2, 9, 4, 8, 9, 3, 9, 0, 1, 7, 5, 8, 6, 4, 8, 3, 1, 3, 9, 3, 0, 2, 4, 5, 8, 0, 6, 1, 2, 0, 5, 4, 7, 5, 6, 3, 9, 5, 8, 1, 5, 9, 3, 4, 7, 7, 6, 6, 0, 8, 6, 2, 5, 2, 1, 5, 8, 5, 0, 1, 3, 9, 7, 4, 3, 3, 5, 9, 3, 7, 0, 1, 5

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• cons

Comments

Equals the Hausdorff dimension of the Sierpinski fractal square-based pyramid, when each square-based pyramid is replaced by 5 half-size such square-based pyramids (see IREM link). - Bernard Schott, Nov 30 2022

Examples

			2.3219280...
		

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..1000
• IREM Paris-Nord, La pyramide de Sierpinski (in French).
• Wikipedia, List of fractals by Hausdorff dimension (see Fractal pyramid).
• Index entries for transcendental numbers

Crossrefs

Cf. decimal expansion of log_2(m): A020857 (m=3), this sequence, A020859 (m=6), A020860 (m=7), A020861 (m=9), A020862 (m=10), A020863 (m=11), A020864 (m=12), A152590 (m=13), A154462 (m=14), A154540 (m=15), A154847 (m=17), A154905 (m=18), A154995 (m=19), A155172 (m=20), A155536 (m=21), A155693 (m=22), A155793 (m=23), A155921 (m=24).

Sierpinski pyramid: A000351 (number of pyramids), A279511 (number of vertices).

Programs

Mathematica

RealDigits[Log[2,5],10,120][[1]] (* Harvey P. Dale, Oct 20 2011 *)

PARI

log(5)/log(2) \\ Charles R Greathouse IV, Aug 06 2020

Extensions

Definition improved by J. Lowell, May 03 2014