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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A211206 Least number which reaches n under the operation introduced in A100787: first differences are the digits of the sequence. 1

%I

%S 1,1,3,1,5,3,7,1,9,5,5,3,3,5,3,1,1,5,3,3,11,5,1,1,3,3,5,5,19,13,1,3,1,

%T 5,7,1,7,1,7,5,5,1,13,3,1,1,11,9,1,5,3,1,3,11,1,9,20,13,3,7,1,3,5,1,5,

%U 9,3,5,9,3,11,1,7,3,11,1,5,1

%N Least number which reaches n under the operation introduced in A100787: first differences are the digits of the sequence.

%C E. Angelini proposes to call Wilsonize(n) the sequence starting with n and having as first differences the digits of the (concatenated) terms of the sequence. Then this sequence lists the smallest starting value a(n)=k such that n is a term of Wilsonize(k).

%H E. Angelini, <a href="http://list.seqfan.eu/pipermail/seqfan/2013-February/010751.html">Smallest hitters</a>, SeqFan list, Feb 04 2013

%o (PARI) A211206(n)={ for(k=1,n, my(seed=k,d=digits(seed)); while(seed<n, seed+=d[1];d=vecextract(concat(d,digits(seed)),"^1"));seed==n&return(k))}

%K nonn,base

%O 1,3

%A _Eric Angelini_ and _M. F. Hasler_, Feb 04 2013

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.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 5 06:51 EST 2020. Contains 338944 sequences. (Running on oeis4.)