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 1-4 of 4 results.

A305793 Restricted growth sequence transform of A305792, a filter sequence constructed from binary expansions of the proper divisors of n.

Original entry on oeis.org

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

Views

Author

Antti Karttunen, Jun 11 2018

Keywords

Crossrefs

Programs

  • PARI
    \\ Needs also code from A286622:
    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; };
    A305792(n) = { my(m=1); fordiv(n,d,if(dA286622(d)-1))); (m); };
    v305793 = rgs_transform(vector(up_to, n, A305792(n)));
    A305793(n) = v305793[n];

Formula

For all i, j:
a(i) = a(j) => A000005(i) = A000005(j).
a(i) = a(j) => A292257(i) = A292257(j).
a(i) = a(j) => A305426(i) = A305426(j).
a(i) = a(j) => A305435(i) = A305435(j).

A305794 a(n) = Product_{d|n, d>1} prime(A286622(d)-1).

Original entry on oeis.org

1, 2, 3, 4, 5, 18, 7, 8, 15, 50, 11, 108, 11, 98, 195, 16, 5, 450, 11, 500, 357, 242, 19, 648, 55, 242, 345, 1372, 19, 76050, 29, 32, 165, 50, 385, 13500, 17, 242, 627, 5000, 17, 254898, 31, 5324, 30225, 722, 37, 3888, 77, 6050, 345, 5324, 31, 238050, 2255, 19208, 627, 722, 41, 29659500, 37, 1682, 76755, 64, 275, 54450, 11, 500, 969, 296450, 19, 405000, 17
Offset: 1

Views

Author

Antti Karttunen, Jun 11 2018

Keywords

Crossrefs

Cf. A008578, A278222, A286622, A305792, A305795 (rgs-transform).
Cf. also A304104.

Programs

  • PARI
    A305794(n) = { my(m=1); fordiv(n, d, if(d>1, m *= prime(A286622(d)-1))); (m); }; \\ Needs also code from A286622.

Formula

a(n) = Product_{d|n, d>1} A008578(A286622(d)).
For all k >= 0, a(2^k) = 2^k.

A317942 a(n) = Product_{d|n, dA286378(d)-1).

Original entry on oeis.org

1, 2, 2, 4, 2, 12, 2, 8, 6, 20, 2, 72, 2, 28, 30, 16, 2, 396, 2, 200, 42, 52, 2, 432, 10, 68, 66, 392, 2, 17100, 2, 32, 78, 92, 70, 26136, 2, 116, 102, 2000, 2, 54684, 2, 1352, 6270, 148, 2, 2592, 14, 3700, 138, 2312, 2, 178596, 130, 5488, 174, 172, 2, 9747000, 2, 188, 14322, 64, 170, 322452, 2, 4232, 222, 289100, 2, 1724976, 2
Offset: 1

Views

Author

Antti Karttunen, Aug 12 2018

Keywords

Crossrefs

Cf. A286378, A317943 (restricted growth sequence transform), A317944.
Cf. also A293216, A305792.

Programs

  • PARI
    \\ Needs also code from A286378:
    A317942(n) = { my(m=1); fordiv(n,d,if(dA286378(d)-1))); (m); };

Formula

a(n) = Product_{d|n, dA008578(A286378(d)).
For all k >= 0, a(2^k) = 2^k.

A305812 a(1) = 0; for n > 1, a(n) = Product_{d|n, 1 < d < n} prime(A305788(d)-1).

Original entry on oeis.org

0, 1, 1, 2, 1, 4, 1, 6, 2, 6, 1, 60, 1, 4, 6, 42, 1, 100, 1, 198, 4, 4, 1, 4620, 3, 4, 10, 60, 1, 4620, 1, 546, 4, 26, 6, 56100, 1, 4, 4, 26334, 1, 600, 1, 60, 210, 10, 1, 1381380, 2, 132, 26, 60, 1, 18700, 6, 4620, 4, 10, 1, 66625020, 1, 4, 60, 15834, 6, 1000, 1, 2418, 10, 3300, 1, 334187700, 1, 4, 84, 60, 4, 2200, 1, 14036022, 110, 4, 1
Offset: 1

Views

Author

Antti Karttunen, Jun 11 2018

Keywords

Crossrefs

Cf. A008578, A278233, A305788, A305813 (rgs-transform), A305814.
Cf. also A305792, A304102.

Programs

  • PARI
    A305812(n) = if(1==n,0, my(m=1); fordiv(n,d,if((d>1)&&(dA305788(d)-1))); (m)); \\ Needs also code from A305788.

Formula

a(1) = 0; for n > 1, a(n) = Product_{d|n, dA008578(A305788(d)).
Showing 1-4 of 4 results.