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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.

A383224 Decimal expansion Sum_{p primes} log(p)^2*p^2/(p^2-1)^2.

Original entry on oeis.org

8, 8, 4, 4, 8, 1, 8, 3, 3, 9, 6, 3, 5, 2, 3, 8, 8, 5, 1, 9, 6, 5, 3, 6, 1, 5, 3, 8, 7, 0, 6, 5, 1, 1, 6, 8, 5, 8, 8, 6, 6, 7, 3, 3, 2, 6, 3, 8, 7, 1, 1, 3, 3, 5, 1, 8, 1, 8, 3, 9, 2, 8, 6, 5, 7, 7, 8, 6, 0, 4, 5, 7, 1, 6, 5, 2, 7, 8, 8, 6, 3, 4, 3, 1, 2, 9, 5, 1, 0, 2, 2, 9, 5, 2, 4, 5, 2, 5, 4, 7, 0, 5, 6, 0, 1
Offset: 0

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Author

Artur Jasinski, Apr 27 2025

Keywords

Examples

			0.8844818339635238851965361...
		

Crossrefs

Cf. A345364.

Programs

  • Maple
    Zeta(2,2)/Zeta(2) -Zeta(1,2)^2/Zeta(2)^2 ; evalf(%) ; # R. J. Mathar, May 07 2025
  • Mathematica
    RealDigits[(6 (-6 Zeta'[2]^2 + Pi^2 Zeta''[2]))/Pi^4, 10, 105][[1]]
  • PARI
    /* Procedure by Bill Allombert */
    default(realprecision, 105);
    SumEulerLog(f,s=1,a=2,d=1)=
    {
      my(p=variable(f));
      if(type(d)!="t_INT",error("incorrect type in SumEulerLog"));
      if (d<0,
        d=-d;
        for(i=1,d, f=deriv(f)*p);
        (-1)^d*intnum(t=1,[oo,log(2)*s],(t-1)^(d-1)*sumeulerrat(f,t*s,a))/gamma(d)
        ,d==0,
        sumeulerrat(f,s,a)
        ,d>0,
        my(S=0,v);
        my(prec=getlocalbitprec());
        f=subst(f,'p,1/p)+O(p^prec);
        for(i=1,d, f=intformal(f/p));
        v = valuation(f,p);
        f = truncate(f);
        for(i=v,prec/(v-1),
         S += polcoef(f,i)*derivnum(t=1,sumeulerrat(1/p,t*i*s,a),d));
        (-1)^d*S);
    }
    SumEulerLog(p^2/(p^2-1)^2,,,2)

Formula

Equals 6*(Pi^2*zeta''(2)-6*zeta'(2)^2)/Pi^4.
Equals 6*(Pi^2*zeta''(2)-6*(zeta[2]*(gamma + log(2*Pi) - 12*log(A)))^2)/Pi^4 where A is Glaisher-Kinkelin constant A074962.
Equals zeta''(2)/zeta(2)-zeta'(2)^2/zeta(2)^2 see A201994, A073002 and A013661.