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A033308 Decimal expansion of Copeland-Erdos constant: concatenate primes. 34
2, 3, 5, 7, 1, 1, 1, 3, 1, 7, 1, 9, 2, 3, 2, 9, 3, 1, 3, 7, 4, 1, 4, 3, 4, 7, 5, 3, 5, 9, 6, 1, 6, 7, 7, 1, 7, 3, 7, 9, 8, 3, 8, 9, 9, 7, 1, 0, 1, 1, 0, 3, 1, 0, 7, 1, 0, 9, 1, 1, 3, 1, 2, 7, 1, 3, 1, 1, 3, 7, 1, 3, 9, 1, 4, 9, 1, 5, 1, 1, 5, 7, 1, 6, 3, 1, 6, 7, 1, 7, 3, 1, 7, 9, 1, 8, 1, 1, 9, 1, 1 (list; constant; graph; refs; listen; history; internal format)
OFFSET

0,1

COMMENTS

The number .23571113171923.... was proved normal in base 10 by Copeland and Erdos but is not known to be normal in other bases. - Jeffrey Shallit, Mar 14 2008

REFERENCES

Copeland, A. H. and Erdos, P. "Note on Normal Numbers." Bull. Amer. Math. Soc. 52, 857-860, 1946.

G. Harman, One hundred years of normal numbers, in M. A. Bennett et al., eds., Number Theory for the Millennium, II (Urbana, IL, 2000), 149-166, A K Peters, Natick, MA, 2002.

Clifford A. Pickover, A Passion for Mathematics, Wiley, 2005; see p. 60.

LINKS

T. D. Noe, Table of n, a(n) for n=0..2000

S. Plouffe, Copeland-Erdos constant, the primes concatenated

S. Plouffe, Copeland-Erdos constant, the primes concatenated

Eric Weisstein's World of Mathematics, Copeland-Erdos Constant

FORMULA

a = Sum[Prime[n]*10^-A068670[n], {n, 1, Infinity}] - Joseph Biberstine (jrbibers(AT)indiana.edu), Aug 12 2006

EXAMPLE

0.235711131719232931374143475359616771737983899710110310710911312...

MATHEMATICA

N[Sum[Prime[n]*10^-(n + Sum[Floor[Log[10, Prime[k]]], {k, 1, n}]), {n, 1, 40}], 100] - Joseph Biberstine (jrbibers(AT)indiana.edu), Aug 12 2006

N[Sum[Prime@n*10^-(n + Sum[Floor[Log[10, Prime@k]], {k, n}]), {n, 45}], 106] - Joseph Biberstine (jrbibers(AT)indiana.edu), Aug 12 2006

IntegerDigits //@ Prime@Range@45 // Flatten (* Robert G. Wilson v Oct 03 2006 *)

PROG

(PARI) { default(realprecision, 2080); x=0.0; m=-1; forprime (p=2, 4000, n=1+floor(log(p)/log(10)); x=p+x*10^n; m+=n; ); x=x/10^m; for (n=0, 2000, d=floor(x); x=(x-d)*10; write("b033308.txt", n, " ", d)); } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Apr 30 2009]

CROSSREFS

Cf. A030168 (continued fraction).

Cf. A072754 (numerators of convergents), A072755 (denominators of convergents).

Cf. also A033307.

Sequence in context: A113493 A060420 A077648 * A134690 A065859 A117819

Adjacent sequences:  A033305 A033306 A033307 * A033309 A033310 A033311

KEYWORD

nonn,cons,base

AUTHOR

Eric Weisstein (eric(AT)weisstein.com)

EXTENSIONS

Fixed my PARI program, had -n Harry J. Smith (hjsmithh(AT)sbcglobal.net), May 19 2009

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.