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 1-5 of 5 results.

A365386 Lexicographically earliest infinite sequence such that a(i) = a(j) => A331410(i) = A331410(j) and A365385(i) = A365385(j) for all i, j >= 1.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Sep 03 2023

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A331410(n), A365385(n)].
For all i, j: A365388(i) = A365388(j) => a(i) = a(j) => A365387(i) = A365387(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; };
    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));
    A331410(n) = if(!bitand(n,n-1),0,1+A331410(n+(n/vecmax(factor(n)[, 1]))));
    A365385(n) = A331410(A163511(n));
    A365386aux(n) = [A331410(n),A365385(n)];
    v365386 = rgs_transform(vector(up_to,n,A365386aux(n)));
    A365386(n) = v365386[n];

A365388 Lexicographically earliest infinite sequence such that a(i) = a(j) => A334867(i) = A334867(i) and A365386(j) = A365386(j) for all i, j >= 1.

Original entry on oeis.org

1, 1, 2, 1, 3, 2, 4, 1, 5, 3, 6, 2, 7, 4, 8, 1, 9, 5, 10, 3, 11, 6, 12, 2, 13, 7, 14, 4, 15, 8, 16, 1, 17, 9, 18, 5, 19, 10, 20, 3, 21, 11, 22, 6, 23, 12, 24, 2, 25, 13, 26, 7, 27, 14, 28, 4, 29, 15, 30, 8, 31, 16, 32, 1, 33, 17, 34, 9, 35, 18, 36, 5, 37, 19, 38, 10, 39, 20, 40, 3, 41, 21, 42, 11, 43, 22, 44, 6, 45, 23, 46, 12, 47, 24, 48, 2, 49, 25, 41
Offset: 1

Views

Author

Antti Karttunen, Sep 07 2023

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A334867(n), A365386(n)], or equally, of the quadruplet [A329697(n), A334204(n), A331410(n), A365385(n)].
For all i, j:
A003602(i) = A003602(j) => a(i) = a(j),
a(i) = a(j) => A334867(i) = A334867(j),
a(i) = a(j) => A335880(i) = A335880(j),
a(i) = a(j) => A365386(i) = A365386(j).

Crossrefs

Differs from A003602 and A351090 for the first time at n=99, where a(99) = 41, while A003602(99) = A351090(99) = 50.

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; };
    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));
    A329697(n) = if(!bitand(n,n-1),0,1+A329697(n-(n/vecmax(factor(n)[, 1]))));
    A334204(n) = A329697(A163511(n));
    A331410(n) = if(!bitand(n,n-1),0,1+A331410(n+(n/vecmax(factor(n)[, 1]))));
    A365385(n) = A331410(A163511(n));
    A365388aux(n) = [A329697(n),A334204(n),A331410(n),A365385(n)];
    v365388 = rgs_transform(vector(up_to,n,A365388aux(n)));
    A365388(n) = v365388[n];

A365395 Lexicographically earliest infinite sequence such that a(i) = a(j) => A365425(i) = A365425(j) and A365427(i) = A365427(j) for all i, j >= 0.

Original entry on oeis.org

1, 1, 1, 2, 1, 3, 2, 4, 1, 5, 3, 6, 2, 7, 4, 2, 1, 8, 5, 9, 3, 10, 6, 3, 2, 11, 7, 7, 4, 12, 2, 4, 1, 13, 8, 14, 5, 15, 9, 5, 3, 16, 10, 11, 6, 17, 3, 6, 2, 18, 11, 10, 7, 19, 7, 7, 4, 17, 12, 20, 2, 7, 4, 21, 1, 22, 13, 23, 8, 24, 14, 8, 5, 25, 15, 18, 9, 26, 5, 9, 3, 27, 16, 16, 10, 28, 11, 10, 6, 29, 17, 30, 3, 10, 6
Offset: 0

Views

Author

Antti Karttunen, Sep 04 2023

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A365425(n), A365427(n)].
Restricted growth sequence transform of the function f(n) = A336390(A163511(n)).
For all i, j: a(i) = a(j) => A365385(i) = A365385(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));
    A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
    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));
    A365425(n) = A046523(A000265(A163511(n)));
    A336467(n) = { my(f=factor(n)); prod(k=1,#f~,if(2==f[k,1],1,(A000265(f[k,1]+1))^f[k,2])); };
    A365427(n) = A336467(A163511(n));
    A365395aux(n) = [A365425(n), A365427(n)];
    v365395 = rgs_transform(vector(1+up_to,n,A365395aux(n-1)));
    A365395(n) = v365395[1+n];

Formula

For all n >= 1, a(n) = a(2*n) = a(A000265(n)).

A366788 a(n) = A366388(A163511(n)).

Original entry on oeis.org

0, 0, 0, 1, 0, 2, 1, 2, 0, 3, 2, 4, 1, 3, 2, 1, 0, 4, 3, 6, 2, 5, 4, 2, 1, 4, 3, 3, 2, 2, 1, 3, 0, 5, 4, 8, 3, 7, 6, 3, 2, 6, 5, 4, 4, 3, 2, 6, 1, 5, 4, 5, 3, 4, 3, 4, 2, 3, 2, 5, 1, 4, 3, 2, 0, 6, 5, 10, 4, 9, 8, 4, 3, 8, 7, 5, 6, 4, 3, 9, 2, 7, 6, 6, 5, 5, 4, 7, 4, 4, 3, 8, 2, 7, 6, 4, 1, 6, 5, 7, 4, 6, 5, 5, 3, 5
Offset: 0

Views

Author

Antti Karttunen, Oct 23 2023

Keywords

Crossrefs

Programs

  • PARI
    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));
    A366388(n) = if(n<=2, 0, if(isprime(n), 1+A366388(primepi(n)), my(f=factor(n)); (apply(A366388, f[, 1])~ * f[, 2])));
    A366788(n) = A366388(A163511(n));

A365387 a(n) = A331410(n) * A331410(A163511(n)).

Original entry on oeis.org

0, 0, 1, 0, 4, 1, 2, 0, 6, 4, 8, 1, 6, 2, 3, 0, 12, 6, 18, 4, 10, 8, 4, 1, 16, 6, 9, 2, 8, 3, 2, 0, 15, 12, 24, 6, 28, 18, 9, 4, 18, 10, 12, 8, 12, 4, 8, 1, 10, 16, 20, 6, 16, 9, 12, 2, 12, 8, 16, 3, 6, 2, 6, 0, 24, 15, 40, 12, 27, 24, 12, 6, 40, 28, 25, 18, 12, 9, 18, 4, 28, 18, 18, 10, 25, 12, 25, 8, 20, 12, 18, 4
Offset: 1

Views

Author

Antti Karttunen, Sep 03 2023

Keywords

Crossrefs

Cf. also A334873.

Programs

Formula

a(n) = A331410(n) * A365385(n).
Showing 1-5 of 5 results.