A103167 a(n) = 2^n mod reverse(2^n).

0, 0, 0, 16, 9, 18, 128, 256, 82, 1024, 2048, 4096, 2356, 16384, 32768, 1980, 131072, 262144, 524288, 1048576, 2097152, 159390, 319770, 16777216, 10108899, 20228688, 134217728, 268435456, 98713642, 1073741824, 2147483648, 4294967296, 2681134876, 17179869184

Offset: 1

Author

Labos Elemer, Jan 28 2005

Keywords

• base
• nonn

Comments

Remainder if 2^n is divided by the reverse of 2^n.

Examples

			a(5) = 2^5 mod reverse(2^5) = 32 mod reverse(32) = 32 mod 23 = 9.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A002113, A071590, A103164-A103167.

Programs

Mathematica

Table[Mod[FromDigits[Reverse[IntegerDigits[2^n]]], 2^n], {n, 1, 256}]
Table[PowerMod[2,n,IntegerReverse[2^n]],{n,40}] (* Harvey P. Dale, Jan 30 2022 *)

Python

def a(n): t = 2**n; return t%int(str(t)[::-1])
print([a(n) for n in range(1, 35)]) # Michael S. Branicky, Dec 12 2021