OFFSET
1,2
COMMENTS
FORMULA
a(n) = Product_{i = 1..Omega(n)} prime(i)^A112798(n,i).
EXAMPLE
Sequence of normalized prime multisets together with the normalized prime multisets of their images begins:
1: {} -> {}
2: {1} -> {1}
3: {2} -> {1,1}
4: {1,1} -> {1,2}
5: {3} -> {1,1,1}
6: {1,2} -> {1,2,2}
7: {4} -> {1,1,1,1}
8: {1,1,1} -> {1,2,3}
9: {2,2} -> {1,1,2,2}
10: {1,3} -> {1,2,2,2}
11: {5} -> {1,1,1,1,1}
12: {1,1,2} -> {1,2,3,3}
13: {6} -> {1,1,1,1,1,1}
14: {1,4} -> {1,2,2,2,2}
15: {2,3} -> {1,1,2,2,2}
16: {1,1,1,1} -> {1,2,3,4}
17: {7} -> {1,1,1,1,1,1,1}
18: {1,2,2} -> {1,2,2,3,3}
MATHEMATICA
Table[With[{y=If[n===1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]]}, Times@@Power[Array[Prime, Length[y]], y]], {n, 100}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 16 2018
STATUS
approved