A165770 Smallest divisor of 123...n (=A007908) larger than the preceding term.

1, 2, 3, 617, 823, 1286, 9721, 14593, 32463, 1234567891, 1417414341, 2110805449, 98220894641, 205761315168520219, 8230452606740808761, 3086419727527803285379, 8755800645468945490437, 70708355728013820970883

Offset

1,2

Comments

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

Links

Table of n, a(n) for n=1..18.

John W. Layman, Re: Sum divides concatenation, SeqFan list, Sep 30 2009.

Prog

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

Crossrefs

Cf. A151995.

Sequence in context: A004887 A240709 A264577 * A226148 A108332 A256115

Adjacent sequences: A165767 A165768 A165769 * A165771 A165772 A165773

Keyword

nonn,base

Author

M. F. Hasler, Sep 30 2009

Extensions

Edited by Charles R Greathouse IV, Apr 24 2010

Status

approved