Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A121805
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A121805 The "commas" sequence: a(1) = 1; for n > 1, let x be the least significant digit of a(n-1); then a(n) = a(n-1) + x*10 + y where y is the most significant digit of a(n) and is the smallest such y, if such a y exists. If no such y exists, stop. +0
2
1, 12, 35, 94, 135, 186, 248, 331, 344, 387, 461, 475, 530, 535, 590, 595, 651, 667, 744, 791, 809, 908, 997, 1068, 1149, 1240, 1241, 1252, 1273, 1304, 1345, 1396, 1457, 1528, 1609, 1700, 1701, 1712, 1733, 1764, 1805, 1856, 1917, 1988, 2070 (list; graph; listen)
OFFSET

1,2

COMMENT

The sequence contains exactly 2137453 terms, with a(2137453)=99999945. The next term does not exist. - Edwin Clark, Dec 11 2006

It is remarkable that the sequence persists for so long. - N. J. A. Sloane (njas(AT)research.att.com), Dec 15 2006

REFERENCES

E. Angelini, "Jeux de suites", in Dossier Pour La Science, pp. 32-35, Volume 59 (Jeux math'), April/June 2008, Paris.

LINKS

Zak Seidov, Table of n, a(n) for n = 1..1001

Eric Angelini, (No title)

EXAMPLE

E.g. a(6) = 186 and a(7) = 248 = 186 + 62

Sequence...:.1,.12,.35,.94,.135,.186,.248,.331,.344,.387,.461,.475,.530,.535,.590,....

Differences:..11..23..59..41...51...62...83...13...43...74...14...55...05...55.....

MAPLE

(Maple program from Edwin Clark): digits:=n->ListTools:-Reverse(convert(n, base, 10)):

nextK:=proc(K) local i, L; for i from 0 to 9 do L:=K+digits(K)[ -1]*10+i; if i = digits(L)[1] then return L; fi; od; FAIL; end:

a:=proc(n) option remember: if n = 1 then return 1; fi; return nextK(a(n-1)); end:

CROSSREFS

Cf. A139284.

Adjacent sequences: A121802 A121803 A121804 this_sequence A121806 A121807 A121808

Sequence in context: A142074 A102085 A058968 this_sequence A103472 A009649 A007794

KEYWORD

nonn,base,fini,nice

AUTHOR

Eric Angelini (Eric.Angelini(AT)kntv.be), Dec 11 2006

EXTENSIONS

More terms from Zak Seidov, Dec 11 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified July 3 11:28 EDT 2009. Contains 160562 sequences.


AT&T Labs Research