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.

A309477 One of the two successive approximations up to 3^n for the 3-adic integer sqrt(-1/2).

Original entry on oeis.org

0, 2, 2, 11, 11, 11, 254, 254, 4628, 11189, 30872, 89921, 444215, 444215, 2038538, 2038538, 30736352, 73783073, 73783073, 848624051, 2010885518, 8984454320, 29905160726, 61286220335, 61286220335, 626145293297, 626145293297, 3168011121626, 10793608606613, 33670401061574
Offset: 0

Views

Author

Seiichi Manyama, Aug 04 2019

Keywords

Examples

			a(1) = (  2)_3 = 2,
a(2) = (  2)_3 = 2,
a(3) = (102)_3 = 11,
a(4) = (102)_3 = 11.
		

Crossrefs

Programs

  • PARI
    {a(n) = if(n, 3^n-truncate(sqrt(-1/2+O(3^n))), 0)}

Formula

a(n) = 3^n - A309476(n) for n > 0.