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

2,1

Comments

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

Links

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

Example

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

Prog

(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
(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

Crossrefs

Cf. A067599, A230625.

Sequence in context: A189290 A129415 A075275 * A319267 A123122 A256680

Adjacent sequences: A245267 A245268 A245269 * A245271 A245272 A245273

Keyword

nonn,base

Author

Chai Wah Wu, Jul 15 2014

Status

approved