A121324 Number of digits in quotient {R_(n*R_n)}/(R_n)^2, where R_n=A002275(n),n*R_n=A053422(n).

1, 19, 328, 4437, 55546, 666655, 7777764, 88888873, 999999982, 11111111091, 122222222200, 1333333333309, 14444444444418, 155555555555527, 1666666666666636, 17777777777777745, 188888888888888854, 1999999999999999963

Offset

1,2

Links

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

Formula

a(n)=round[log_10{9*(10^(n*(10^n - 1)/9) - 1)/(10^n - 1)^2}]

Mathematica

f[n_] := Floor[n(10^n - 1)/9 - 2n + Log[10, 9] + If[n == 1, 2, 1]]; Array[f, 18] (* Robert G. Wilson v, Aug 27 2006 *)

Crossrefs

Sequence in context: A015676 A098304 A014900 * A093973 A345963 A202043

Adjacent sequences: A121321 A121322 A121323 * A121325 A121326 A121327

Keyword

nonn,base

Author

Lekraj Beedassy, Aug 26 2006

Extensions

More terms from Robert G. Wilson v, Aug 27 2006

Status

approved