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 1-3 of 3 results.

A323174 Deficiency computed for conjugated prime factorization: a(n) = A033879(A122111(n)).

Original entry on oeis.org

1, 1, 1, 2, 1, 0, 1, 4, 5, -4, 1, 2, 1, -12, -3, 6, 1, 6, 1, -2, -19, -28, 1, 4, 14, -60, 19, -10, 1, -12, 1, 10, -51, -124, -12, 10, 1, -252, -115, 0, 1, -48, 1, -26, 7, -508, 1, 8, 41, 12, -243, -58, 1, 22, -64, -8, -499, -1020, 1, -12, 1, -2044, -17, 12, -168, -120, 1, -122, -1011, -54, 1, 18, 1, -4092, 26, -250, -39, -264, 1, 4
Offset: 1

Views

Author

Antti Karttunen, Jan 10 2019

Keywords

Comments

Zeros occur at A122111(A000396(k)), k >= 1: 6, 40, 11264, 18253611008, ...

Crossrefs

Programs

  • Mathematica
    A122111[n_] := Product[Prime[Sum[If[jA122111[n]}, 2k - DivisorSigma[1, k]];
    Array[a, 80] (* Jean-François Alcover, Sep 23 2020 *)
  • PARI
    A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
    A122111(n) = if(1==n,n,prime(bigomega(n))*A122111(A064989(n)));
    A323174(n) = { my(k=A122111(n)); ((2*k)-sigma(k)); }

Formula

a(n) = A033879(A122111(n)).
a(n) = 2*A122111(n) - A323173(n).

A323248 a(n) = A323247(n) - A323243(n).

Original entry on oeis.org

0, 0, 0, 0, 0, 2, 0, 3, -2, 3, 0, 7, 0, 14, 0, 2, 0, 9, 0, 15, -5, 16, 0, 18, -6, 44, 1, 19, 0, 7, 0, 25, 12, 80, -4, 10, 0, 254, -14, 18, 0, 33, 0, 63, 5, 224, 0, 41, -14, 16, 6, 127, 0, 24, -21, 66, -14, 746, 0, 38, 0, 1360, 13, 16, 8, 39, 0, 211, 252, 37, 0, 33, 0, 3836, 7, 403, -12, 103, 0, 73, -16, 5456, 0, 22, -74, 12248, -350, 26, 0, 8
Offset: 1

Views

Author

Antti Karttunen, Jan 10 2019

Keywords

Crossrefs

Programs

Formula

a(n) = A323247(n) - A323243(n).
a(n) = A323244(n) - A001222(n).
For n > 1, a(n) = A294898(A156552(n)).

A323168 Lexicographically earliest sequence such that for all i, j, a(i) = a(j) => f(i) = f(j), where f(n) = [A322867(n), A323174(n)] for n > 1, and f(1) = 0.

Original entry on oeis.org

1, 2, 2, 3, 2, 4, 2, 5, 6, 7, 2, 3, 2, 8, 9, 10, 2, 11, 2, 12, 13, 14, 2, 15, 16, 17, 18, 19, 2, 20, 2, 21, 22, 23, 20, 21, 2, 24, 25, 26, 2, 27, 2, 28, 29, 30, 2, 31, 32, 33, 34, 35, 2, 36, 37, 38, 39, 40, 2, 41, 2, 42, 43, 44, 45, 46, 2, 47, 48, 49, 2, 50, 2, 51, 52, 53, 54, 55, 2, 15, 32, 56, 2, 57, 58, 59, 60, 61, 2, 62, 63, 64, 65, 66, 67, 21, 2, 68, 69, 70, 2, 71, 2, 57
Offset: 1

Views

Author

Antti Karttunen, Jan 10 2019

Keywords

Comments

Restricted growth sequence transform of function f, with f(1) = 0 and f(n) = [A322867(n), A323174(n)] for n > 1.
Equally, restricted growth sequence transform of function f, with f(1) = 0 and f(n) = A318310(A122111(n)) for n > 1.
For all i, j:
a(i) = a(j) => A322867(i) = A322867(j),
a(i) = a(j) => A323167(i) = A323167(j),
a(i) = a(j) => A323174(i) = A323174(j).

Crossrefs

Programs

  • PARI
    up_to = 4096;
    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; };
    A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
    A122111(n) = if(1==n,n,prime(bigomega(n))*A122111(A064989(n)));
    A005187(n) = { my(s=n); while(n>>=1, s+=n); s; };
    A294898(n) = (A005187(n)-sigma(n));
    A318310aux(n) = [hammingweight(n), A294898(n)];
    A323168aux(n) = if(1==n,0,A318310aux(A122111(n)));
    v323168 = rgs_transform(vector(up_to, n, A323168aux(n)));
    A323168(n) = v323168[n];
Showing 1-3 of 3 results.