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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.

A346234 Dirichlet inverse of A003961, where A003961(n) is fully multiplicative with a(prime(k)) = prime(k+1).

Original entry on oeis.org

1, -3, -5, 0, -7, 15, -11, 0, 0, 21, -13, 0, -17, 33, 35, 0, -19, 0, -23, 0, 55, 39, -29, 0, 0, 51, 0, 0, -31, -105, -37, 0, 65, 57, 77, 0, -41, 69, 85, 0, -43, -165, -47, 0, 0, 87, -53, 0, 0, 0, 95, 0, -59, 0, 91, 0, 115, 93, -61, 0, -67, 111, 0, 0, 119, -195, -71, 0, 145, -231, -73, 0, -79, 123, 0, 0, 143, -255, -83, 0, 0, 129
Offset: 1

Views

Author

Antti Karttunen, Jul 11 2021

Keywords

Crossrefs

Programs

  • PARI
    up_to = 16384;
    DirInverseCorrect(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = (-u[1]*sumdiv(n, d, if(dA003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
    v346234 = DirInverseCorrect(vector(up_to,n,A003961(n)));
    A346234(n) = v346234[n];
    
  • PARI
    A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
    A346234(n) = (moebius(n)*A003961(n));
    
  • PARI
    A346234(n) = { my(f = factor(n)); prod(i=1, #f~, if(1Antti Karttunen, Nov 14 2021

Formula

a(n) = A055615(A003961(n)).
a(n) = A008683(n) * A003961(n).
Multiplicative with a(p^e) = 0 if e > 1, and -nextprime(p) otherwise, where nextprime function is A151800. - Antti Karttunen, Nov 14 2021

Extensions

Keyword:mult added by Antti Karttunen, Nov 14 2021