

A159862


Main diagonal of A159861.


2




OFFSET

1,3


COMMENTS

The length (number of decimal digits) of a(n) may be a power of 2 and often simply doubles, when n is increased by 1. But there are many exceptions: n = 11, 12, 13 give lengths 2^8, 3*2^7, 2^9, respectively. A factor of 3 is found in the lengths of a(n) for n = 12, 112..123, 1113..1234, 11123..12345, and so on. A factor of 7 is found for n = 1112, 11112..11122, and so on. 15 is factor of the length of a(11111112).


LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..12


MAPLE

R:= (S, m)> iquo(S+m1, m):
A:= proc(m, n) option remember; `if`(n=1, 1,
R(parse(cat(seq(A(m, j), j=1..n1))), m))
end:
a:= n> A(n, n):
seq(a(n), n=1..10);


CROSSREFS

Cf. A156146, A156147, A000040, A010783.
Sequence in context: A166168 A126559 A213795 * A298648 A164820 A022387
Adjacent sequences: A159859 A159860 A159861 * A159863 A159864 A159865


KEYWORD

easy,nonn


AUTHOR

Eric Angelini and Alois P. Heinz, Apr 24 2009


STATUS

approved



