A083872 -id:A083872 - cp's OEIS frontend

A119628 Inverse permutation to sequence A083872.

1, 2, 3, 5, 9, 4, 31, 6, 17, 10, 271, 7, 793, 32, 11, 18, 5377, 19, 14689, 12, 33, 272, 96001, 8, 161, 794, 97, 34, 917281, 13, 2332801, 61, 273, 5378, 35, 20, 19595521, 14690, 795, 14, 102435841, 36, 258048001, 274, 21, 96002, 1258709761, 22, 1585, 162, 5379

Offset: 1

Leroy Quet, Jun 08 2006

nonn

Rémy Sigrist, Table of n, a(n) for n = 1..10000

Cf. A027423, A083872.

{m=31;v=[];for(n=1,m,v=concat(v,vecsort(eval(setminus(Set(divisors(n!)),Set(v))))));z=100;u=vector(z);for(j=1,#v,if(v[j]<=z,u[v[j]]=j));i=1;while(u[i]>0,print1(u[i],",");i++)} \\ Klaus Brockhaus, Aug 16 2006

a(n) = my (ff=1, f=1); for (i=1, oo, f*=i; if (f%n==0, return (numdiv(ff) + sum(j=1, n, ff%j!=0 && f%j == 0))); ff=f) \\ Rémy Sigrist, Nov 08 2018

a(p) = A027423(p-1) + 1 for any prime number p. - Rémy Sigrist, Nov 08 2018

a(11) to a(36) from Klaus Brockhaus, Aug 16 2006

More terms from Rémy Sigrist, Nov 08 2018

A110797 a(0) = 1, a(1) = 2; then all the products generated by these numbers, then the next number 3 and so on.

Original entry on oeis.org

1, 2, 3, 6, 4, 8, 12, 24, 5, 10, 15, 20, 30, 40, 60, 120, 6, 12, 18, 24, 30, 36, 48, 60, 72, 90, 120, 144, 180, 240, 360, 720, 7, 14, 21, 28, 35, 42, 42, 56, 70, 84, 84, 105, 126, 140, 168, 168, 210, 210, 252, 280, 336, 420, 420, 504, 630, 840, 840, 1008, 1260, 1680

Offset: 0

Amarnath Murthy, Aug 13 2005

nonn

a(2^n) = n+2.
Differs from A083872 starting at a(16)=6.
"All the products generated by these numbers" means "the product of the most recently added singleton with each of the previous terms, sorted by size." - Joel B. Lewis, Nov 15 2006

Ivan Neretin, Table of n, a(n) for n = 0..1023

a = {1, 2}; Do[a = Join[a, Sort[n*a]], {n, 3, 7}]; a (* Ivan Neretin, May 09 2015 *)

Extended by Ray Chandler, Aug 23 2005

cp's OEIS Frontend

A119628 Inverse permutation to sequence A083872.

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