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A213007 Decimal expansion of Brun's quadruple primes constant. 2
8, 7, 0, 5, 8, 8, 3, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
Infinite sum of the reciprocals of p, p+2, p+6, and p+8, where p ranges over all elements of A007530.
The 9th digit is probably 0.
LINKS
Wikipedia, Brun's theorem.
Wikipedia, Prime quadruplet.
FORMULA
Sum_{n >= 1} (1/c(n) + 1/(c(n)+2) + 1/(c(n)+6) + 1/(c(n)+8)), where c(n) = A007530(n).
EXAMPLE
0.8705883800[+-5]
CROSSREFS
Sequence in context: A330142 A198112 A358938 * A155094 A369633 A294969
KEYWORD
nonn,cons,hard,more
AUTHOR
Stanislav Sykora, Jun 01 2012
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)