A038490 Sums of 2 distinct powers of 11.

12, 122, 132, 1332, 1342, 1452, 14642, 14652, 14762, 15972, 161052, 161062, 161172, 162382, 175692, 1771562, 1771572, 1771682, 1772892, 1786202, 1932612, 19487172, 19487182, 19487292, 19488502, 19501812, 19648222, 21258732, 214358882, 214358892, 214359002, 214360212, 214373522, 214519932, 216130442

Offset: 1

Author

Olivier Gérard

Keywords

• nonn
• easy

Links

• Robert Israel, Table of n, a(n) for n = 1..10000

Crossrefs

Base 11 interpretation of A038444.

Programs

Maple

seq(seq(11^i+11^j,i=0..j-1),j=1..10); # Robert Israel, Jun 21 2018

Mathematica

Take[Union[Plus@@@Subsets[11^Range[0,20],{2}]],50] (* Harvey P. Dale, Dec 16 2010 *)

Python

from math import isqrt
def A038490(n): return 11**(m:=isqrt(n<<3)+1>>1)+11**(n-1-(m*(m-1)>>1)) # Chai Wah Wu, Apr 04 2025

Extensions

More terms from Vincenzo Librandi, Aug 06 2009

a(33)=214373522 inserted by Robert Israel, Jun 21 2018