A284799 Write in base k, complement, reverse. Case k = 4.

3, 2, 1, 0, 14, 10, 6, 2, 13, 9, 5, 1, 12, 8, 4, 0, 62, 46, 30, 14, 58, 42, 26, 10, 54, 38, 22, 6, 50, 34, 18, 2, 61, 45, 29, 13, 57, 41, 25, 9, 53, 37, 21, 5, 49, 33, 17, 1, 60, 44, 28, 12, 56, 40, 24, 8, 52, 36, 20, 4, 48, 32, 16, 0, 254, 190, 126, 62, 238, 174

Offset: 0

Author

Paolo P. Lava, Apr 03 2017

Keywords

• nonn
• base
• easy
• look

Examples

			a(16) = 62 because 16 in base 4 is 100, its complement in base 4 is 233 and the digit reverse is 332 that is 64 in base 10.
		

Links

• Robert Israel, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A036044, A267193, A284800.

Programs

Maple

P:=proc(q,h) local a,b,k,n; print(h-1); for n from 1 to q do a:=convert(n,base,h); b:=0;
for k from 1 to nops(a) do a[k]:=h-1-a[k]; b:=h*b+a[k]; od; print(b); od; end: P(10^2,4);

Mathematica

With[{k = 4}, Array[FromDigits[Reverse[k - IntegerDigits[#, k] - 1], k] &, 70, 0]] (* Michael De Vlieger, Feb 04 2022 *)

Python

from gmpy2 import digits
def A284799(n): return -int((s:=digits(n,4)[::-1]),4)-1+4**len(s) # Chai Wah Wu, Feb 04 2022

Formula

a(a(n))=n unless n == 3 (mod 4). - Robert Israel, Apr 01 2020