A245270 Like A067599 but write everything in binary, then display the answer in base 10.

5, 7, 10, 11, 47, 15, 11, 14, 91, 23, 87, 27, 95, 123, 20, 35, 94, 39, 171, 127, 183, 47, 95, 22, 187, 15, 175, 59, 763, 63, 21, 247, 355, 191, 174, 75, 359, 251, 187, 83, 767, 87, 343, 235, 367, 95, 167, 30, 182, 483, 347, 107, 95, 375, 191, 487, 379, 119

Offset: 2

Author

Chai Wah Wu, Jul 15 2014

Keywords

• nonn
• base

Comments

The only fixed point < 10^8 is 470367 = 3^4 * 5807^1. - Christopher Scussel, Apr 28 2025

Examples

			24 = 2^3 * 3^1 has binary encoding 10_11_11_1, that is, 95 in decimal.
		

Links

• Chai Wah Wu, Table of n, a(n) for n = 2..10000

Crossrefs

Cf. A067599, A230625.

Programs

PARI

a(n) = {f = factor(n); s = []; for (i=1, #f~, s = concat(s, binary(f[i, 1])); s = concat(s, binary(f[i, 2]));); subst(Pol(s), x, 2);} \\ Michel Marcus, Jul 16 2014

Python

import sympy
[int(''.join([bin(y)[2:] for x in sorted(sympy.ntheory.factorint(n).items()) for y in x]),2) for n in range(2,200)] # compute a(n) for n > 1
# Chai Wah Wu, Jul 15 2014