login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A323883
Dirichlet inverse of A322026.
4
1, -2, -3, 0, -1, 7, -1, 2, 2, 2, -1, 0, -1, 2, 3, -1, -1, -6, -1, 0, 3, 2, -1, -11, 0, 2, 3, 0, -1, -7, -1, -1, 3, 2, 1, -1, -1, 2, 3, -2, -1, -7, -1, 0, -2, 2, -1, 7, 0, 0, 3, 0, -1, -9, 1, -2, 3, 2, -1, 0, -1, 2, -2, 3, 1, -7, -1, 0, 3, -2, -1, 20, -1, 2, 0, 0, 1, -7, -1, 1, -6, 2, -1, 0, 1, 2, 3, -2, -1, 6, 1, 0, 3, 2, 1, 8
OFFSET
1,2
LINKS
PROG
(PARI)
up_to = 65537;
rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };
A007814(n) = valuation(n, 2);
A007949(n) = valuation(n, 3);
v322026 = rgs_transform(vector(up_to, n, [A007814(n), A007949(n)]));
DirInverse(v) = { my(u=vector(#v)); u[1] = (1/v[1]); for(n=2, #v, u[n] = -sumdiv(n, d, if(d<n, v[n/d]*u[d], 0))); (u) }; \\ Compute the Dirichlet inverse of the sequence given in input vector v.
v323883 = DirInverse(v322026);
A323883(n) = v323883[n];
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Feb 08 2019
STATUS
approved

  NODES
COMMUNITY 1
INTERN 1