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A138142 Nonnegative numbers with digits in descending order that differ exactly by 1. 2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 21, 32, 43, 54, 65, 76, 87, 98, 210, 321, 432, 543, 654, 765, 876, 987, 3210, 4321, 5432, 6543, 7654, 8765, 9876, 43210, 54321, 65432, 76543, 87654, 98765, 543210, 654321, 765432, 876543, 987654 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

This finite sequence has 55 members. The last member is 9876543210. There are 11-k members with k digits. See A052016 for primes in this sequence. All members with 3 or more digits are straight-line numbers A135643.

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

Last 10 members of this finite sequence:

a(45)=6543210

a(46)=7654321

a(47)=8765432

a(48)=9876543

a(49)=76543210

a(50)=87654321

a(51)=98765432

a(52)=876543210

a(53)=987654321

a(54)=9876543210

MATHEMATICA

fQ[n_]:=Module[{id=IntegerDigits[n]}, n<10 || Union[Differences[id]]=={-1}]; Select[Range[0, 100000], fQ] (* Vladimir Joseph Stephan Orlovsky, Dec 29 2010 *)

Sort[Flatten[With[{t=Range[9, 0, -1]}, Table[FromDigits/@Partition[t, n, 1], {n, 10}]]]] (* Harvey P. Dale, Oct 31 2013 *)

CROSSREFS

Cf. A052016, A135643, A138141.

Sequence in context: A158699 A247107 A061511 * A085890 A274842 A134817

Adjacent sequences:  A138139 A138140 A138141 * A138143 A138144 A138145

KEYWORD

base,easy,fini,nonn

AUTHOR

Omar E. Pol, Mar 19 2008

EXTENSIONS

Examples corrected by Omar E. Pol, Dec 06 2008

STATUS

approved

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Last modified May 23 18:45 EDT 2019. Contains 323528 sequences. (Running on oeis4.)