A033906 Sort then Add, a(1)=20.

20, 22, 44, 88, 176, 343, 677, 1354, 2699, 5398, 8987, 16876, 33554, 67009, 67688, 134476, 268943, 503632, 526988, 783877, 1161665, 2277331, 3500708, 3504286, 3738854, 7084642, 7329320, 7552699, 10109498, 10224397, 11447876, 22894654

Offset

1,1

Links

Table of n, a(n) for n=1..32.

Formula

a(n)=A033905(n-1), n>2. [From R. J. Mathar, Oct 22 2008]

Maple

A033906 := proc(n)
    option remember ;
    if n =1 then
        20;
    else
        A070196(procname(n-1)) ;
    end if;
end proc:
seq(A033906(n), n=1..100) ; # R. J. Mathar, Feb 03 2025

Mathematica

NestList[#+FromDigits[Sort[IntegerDigits[#]]]&, 20, 40] (* Harvey P. Dale, Oct 28 2017 *)

Crossrefs

Cf. A033860.

Sequence in context: A133260 A163630 A259735 * A367620 A322323 A139357

Adjacent sequences: A033903 A033904 A033905 * A033907 A033908 A033909

Keyword

nonn,base,easy,changed

Author

N. J. A. Sloane, David W. Wilson

Status

approved