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.

A373462 Decimal expansion of the number whose base-3 expansion is A004601, the base-2 expansion of Pi.

Original entry on oeis.org

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

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Author

M. F. Hasler, Jul 17 2024

Keywords

Comments

This number is likely to be normal in base 2 but certainly not normal in base 3, where it has only digits 0 and 1.

Examples

			Pi = 3.14159...[10] = 11.001001000011111101...[2] (i.e., in base 2, cf. A004601), which, considered as the base-3 expansion of a constant c = 3 + 1 + 1/3^3 + 1/3^6 + ... = 4.0384...[10]
		

Crossrefs

Cf. A000796 (decimal expansion of Pi), A004601 (binary expansion of Pi).

Programs

  • PARI
    localprec(10+ N=99); d = concat(binary(Pi)); c = sum(k=1, #d, d[k]*3^(2-k),.); digits(c*10^N\1) /* if you use localprec() make sure all code is in the same scope */

Formula

4.03841723862712010342364922592921866745315784013953355342337019359450160810479...