A038558 Smallest number with derivative n.

0, 2, 4, 5, 8, 9, 11, 10, 16, 17, 19, 18, 23, 22, 20, 21, 32, 33, 35, 34, 39, 38, 36, 37, 47, 46, 44, 45, 40, 41, 43, 42, 64, 65, 67, 66, 71, 70, 68, 69, 79, 78, 76, 77, 72, 73, 75, 74, 95, 94, 92, 93, 88, 89, 91, 90, 80, 81, 83, 82, 87, 86, 84, 85, 128, 129, 131, 130, 135, 134

Offset

0,2

Links

Reinhard Zumkeller, Table of n, a(n) for n = 0..10000

Mathematica

dtn[ L_ ] := Fold[ 2#1+#2&, 0, L ]; h[ n_ ] := dtn[ {1}~Join~Table[ Mod[ 1+Apply[ Plus, Take[ IntegerDigits[ n, 2 ], k ] ], 2 ], {k, 1, Length[ IntegerDigits[ n, 2 ] ]} ] ]; Table[ h[ n ], {n, 100} ]

Prog

(Haskell)
import Data.List (elemIndex)
import Data.Maybe (fromJust)
a038558 = fromJust . (`elemIndex` a038554_list)
-- Reinhard Zumkeller, Mar 06 2013

Crossrefs

Cf. A038554-A038556.

Sequence in context: A267703 A377568 A277075 * A286031 A027883 A201818

Adjacent sequences: A038555 A038556 A038557 * A038559 A038560 A038561

Keyword

nonn,nice,easy

Author

N. J. A. Sloane

Extensions

More terms from Erich Friedman

a(0)=0 added and offset adjusted by Reinhard Zumkeller, Mar 06 2013

Status

approved