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A133017 Decimal expansion of the constant formed by concatenating the imperfect numbers. 0
1, 2, 3, 4, 5, 7, 8, 9, 1, 0, 1, 1, 1, 2, 1, 3, 1, 4, 1, 5, 1, 6, 1, 7, 1, 8, 1, 9, 2, 0, 2, 1, 2, 2, 2, 3, 2, 4, 2, 5, 2, 6, 2, 7, 2, 9, 3, 0, 3, 1, 3, 2, 3, 3, 3, 4, 3, 5, 3, 6, 3, 7, 3, 8, 3, 9, 4, 0, 4, 1, 4, 2, 4, 3, 4, 4, 4, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

A theorem of Copeland & Erdős proves that this constant is 10-normal. - Charles R Greathouse IV, Feb 06 2015

LINKS

Table of n, a(n) for n=0..77.

A. H. Copeland and P. Erdős, Note on normal numbers, Bull. Amer. Math. Soc. 52 (1946), pp. 857-860.

EXAMPLE

0.12345789101112131415161718192021222324252627293031...

PROG

(PARI) print1(1); for(n=2, 45, if(sigma(n, -1)!=2, d=digits(n); for(i=1, #d, print1(", "d[i])))) \\ Charles R Greathouse IV, Feb 06 2015

CROSSREFS

Cf. A007376, A033307, A033308, A079718. Imperfect numbers: A132999.

Sequence in context: A305077 A302175 A228683 * A290019 A161924 A034153

Adjacent sequences:  A133014 A133015 A133016 * A133018 A133019 A133020

KEYWORD

cons,easy,nonn,base

AUTHOR

Omar E. Pol, Oct 20 2007

STATUS

approved

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Last modified February 28 00:58 EST 2020. Contains 332319 sequences. (Running on oeis4.)