cp's OEIS Frontend

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.

Showing 1-2 of 2 results.

A365467 Lexicographically earliest infinite sequence such that a(i) = a(j) => A336467(i) = A336467(j) and A336467(A163511(i)) = A336467(A163511(j)) for all i, j >= 1, where A336467 is fully multiplicative with a(2) = 1 and a(p) = oddpart(p+1) for odd primes p.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 3, 1, 1, 2, 4, 1, 5, 3, 2, 1, 6, 1, 7, 2, 8, 4, 2, 1, 9, 5, 3, 3, 10, 2, 3, 1, 2, 6, 11, 1, 12, 7, 13, 2, 14, 8, 15, 4, 2, 2, 4, 1, 3, 9, 16, 5, 17, 3, 9, 3, 18, 10, 19, 2, 20, 3, 21, 1, 22, 2, 23, 6, 11, 11, 6, 1, 24, 12, 9, 7, 2, 13, 7, 2, 8, 14, 14, 8, 17, 15, 19, 4, 25, 2, 26, 2, 8, 4, 27, 1, 28, 3
Offset: 1

Views

Author

Antti Karttunen, Sep 04 2023

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A336467(n), A365427(n)].
For all i, j: A003602(i) = A003602(j) => a(i) = a(j).

Crossrefs

Programs

  • 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; };
    A000265(n) = (n>>valuation(n,2));
    A163511(n) = if(!n, 1, my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
    A336467(n) = { my(f=factor(n)); prod(k=1,#f~,if(2==f[k,1],1,(A000265(f[k,1]+1))^f[k,2])); };
    A365467aux(n) = [A336467(n), A336467(A163511(n))];
    v365467 = rgs_transform(vector(up_to,n,A365467aux(n)));
    A365467(n) = v365467[n];

A366381 Lexicographically earliest infinite sequence such that a(i) = a(j) => A336466(i) = A336466(j) and A336467(i) = A336467(j) for all i, j >= 1, where A336466 is fully multiplicative with a(p) = oddpart(p-1) for any prime p and A336467 is fully multiplicative with a(2) = 1 and a(p) = oddpart(p+1) for odd primes p.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 3, 1, 1, 2, 4, 1, 5, 3, 2, 1, 6, 1, 7, 2, 3, 4, 8, 1, 6, 5, 1, 3, 9, 2, 10, 1, 4, 6, 11, 1, 12, 7, 5, 2, 13, 3, 14, 4, 2, 8, 15, 1, 16, 6, 6, 5, 17, 1, 18, 3, 7, 9, 19, 2, 20, 10, 3, 1, 21, 4, 22, 6, 8, 11, 23, 1, 24, 12, 6, 7, 25, 5, 26, 2, 1, 13, 27, 3, 28, 14, 9, 4, 29, 2, 30, 8, 10, 15, 31, 1, 32
Offset: 1

Views

Author

Antti Karttunen, Oct 12 2023

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A336466(n), A336467(n)].
For all i, j: A003602(i) = A003602(j) => A366380(i) = A366380(j) => a(i) = a(j).

Crossrefs

Programs

  • 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; };
    A000265(n) = (n>>valuation(n,2));
    A336466(n) = { my(f=factor(n)); prod(k=1, #f~, A000265(f[k, 1]-1)^f[k, 2]); };
    A336467(n) = { my(f=factor(n)); prod(k=1,#f~,if(2==f[k,1],1,(A000265(f[k,1]+1))^f[k,2])); };
    A366381aux(n) = [A336466(n), A336467(n)];
    v366381 = rgs_transform(vector(up_to,n,A366381aux(n)));
    A366381(n) = v366381[n];
Showing 1-2 of 2 results.