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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A165132 Primes whose logarithms are known to possess ternary BBP formulas.

Original entry on oeis.org

2, 3, 5, 7, 11, 13
Offset: 1

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Author

Jaume Oliver Lafont, Sep 04 2009

Keywords

Comments

From Jaume Oliver Lafont, Oct 07 2009: (Start)
log(2)=(2/3)P(1,9,2,(1,0))
log(3)=(1/9)P(1,9,2,(9,1))
log(5)=(4/27)P(1,3^4,4,(9,3,1,0))
log(7)=(1/3^5)P(1,3^6,6,(405,81,72,9,5,0))
log(11)=(1/(2*3^9))P(1,3^10,10,(85293,10935,9477,1215,648,135,117,15,13,0))
log(13)=(1/3^5)P(1,3^6,6,(567,81,36,9,7,0))
See the link for the definition of P notation.
Equivalent expressions in reduced coefficients are given in the code section.
(End)

Crossrefs

Cf. A104885.

Programs

  • PARI
    \\ Jaume Oliver Lafont, Oct 07 2009
    log2=2*suminf(k=1,[0,1][k%2+1]/k/3^k)
    log3=suminf(k=1,[1,3][k%2+1]/k/3^k)
    log5=4*suminf(k=1,[0,1,1,1][k%4+1]/k/3^k)
    log7=suminf(k=1,[0,5,3,8,3,5][k%6+1]/k/3^k)
    log11=suminf(k=1,[0,13,5,13,5,8,5,13,5,13][k%10+1]/k/3^k)/2
    log13=suminf(k=1,[0,7,3,4,3,7][k%6+1]/k/3^k)