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Smallest divisor of 123...n (=A007908) larger than the preceding term.
3

%I #11 Dec 23 2024 14:53:42

%S 1,2,3,617,823,1286,9721,14593,32463,1234567891,1417414341,2110805449,

%T 98220894641,205761315168520219,8230452606740808761,

%U 3086419727527803285379,8755800645468945490437,70708355728013820970883

%N Smallest divisor of 123...n (=A007908) larger than the preceding term.

%C Inspired by Layman's comment on a sequence from Angelini, cf. link.

%H John W. Layman, <a href="https://web.archive.org/web/*/http://list.seqfan.eu/oldermail/seqfan/2009-September/002434.html">Re: Sum divides concatenation</a>, SeqFan list, Sep 30 2009.

%o (PARI) c=""; s=0; for(i=1,19, fordiv(c=eval(Str(c,i)),d, d>s || next; print1(s=d,", "); break))

%Y Cf. A151995.

%K nonn,base

%O 1,2

%A _M. F. Hasler_, Sep 30 2009

%E Edited by _Charles R Greathouse IV_, Apr 24 2010