The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A052191 Smallest multiple of n with no isolated digits. 2
 11, 22, 33, 44, 55, 66, 77, 88, 99, 1100, 11, 444, 1144, 3388, 555, 2288, 1122, 666, 2299, 1100, 777, 22, 2277, 888, 1100, 1144, 999, 3388, 2233, 3300, 4433, 6688, 33, 1122, 1155, 1188, 111, 3344, 5577, 2200, 2255, 5544, 3311, 44, 4455, 5566, 7755 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) = n * A052192(n). LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 EXAMPLE a(23)=2277 since 23*99=2277 and all the digits of 2277 have a neighboring digit which is the same. MATHEMATICA isol[n_ ] := Module[{}, L={11}~Join~IntegerDigits[n ]~Join~{11}; l=Length[L ]; Apply[And, Table[L[[i ] ]==L[[i-1 ] ]||L[[i ] ]==L[[i+1 ] ], {i, 2, l-1} ] ] ] a[n_ ] := a[n ]=Module[{}, m=0; While[Not[isol[m ] ], m=m+n ]; m ] Table[a[i ], {i, 1, 100} ] smn[n_]:=Module[{k=1}, While[Min[Length/@Split[IntegerDigits[k*n]]]<2, k++]; k*n]; Array[smn, 50] (* Harvey P. Dale, Oct 19 2018 *) PROG (Haskell) import Data.List (group) a052191 n = head \$    filter ((> 1) . minimum . map length . group . show) \$ [0, n..] -- Reinhard Zumkeller, Sep 15 2011 (Python) def A052191(n):     k = 0     while True:         k += n         x = split('(0+|1+|2+|3+|4+|5+|6+|7+|8+|9+)', str(k))         for d in x:             if len(d) == 1:                 break         else:             return k # Chai Wah Wu, Jan 03 2015 CROSSREFS Sequence in context: A110745 A280826 A020338 * A321536 A110732 A044836 Adjacent sequences:  A052188 A052189 A052190 * A052192 A052193 A052194 KEYWORD base,easy,nice,nonn,look AUTHOR Erich Friedman, Jan 28 2000 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 25 16:39 EDT 2021. Contains 346291 sequences. (Running on oeis4.)