PPS perfect number
y.kohmoto
zbi74583 at boat.zero.ad.jp
Mon Nov 22 07:39:48 CET 2004
Hello, Farideh.
Thanks you for the calculation of Prime power sigma perfect number.
I mean that A096290 is "Primitive" Prime power sigma perfect number
The non-primitive PPSigma-perfect numbers are obtained from the
primitive ones by multiplying by m, if m is the form : Product p_i^2 and
relatively prime to the primitive PPSigma-perfect number.
Your example :
5400=2^3*3^3*5^2 is represented as {Primitive PPSigma-perfect
number=2^3*3^3}*{p^2=5^2}
These examples are not so interesting.
Generally, Mathematicians don't count non-primitive solutions.
But I think OEIS should have both sequences :
%I A096290
%S A096290 216,5400,10584,26136,36504,62424,77976,114264,181656,207576,
%T A096290
264600,295704,363096,399384,477144,606744,653400,751896,803736
%U A096290 912600,969624,1088856,1149984,1151064,1280664,1348056,1488024
%N A096290 Prime power sigma perfect number.
%C A096290 Farideh Firoozbakht caluculated most of terms.
%Y A096290 A000001
%K A096290 nonn
%O A096290 1, 1
%A A096290 Yasutoshi Kohmoto (zbi74583 at boat.zero.ad.jp)
%I A000001
%S A000001 216, 1149984, 365727111552, 1590733122516339863159808000
%N A000001 Primitive prime power sigma perfect number.
If n=Product p_i^r_i
then PPsigma(n)= Product {Sum p_i^s_i , 2<=s_i<=r_i ,
s_i is prime}
PPsigma(n)=2*n
%e A000001 PPsigma(2^5*3^3)=(2^2+2^3+2^5)*(3^2+3^3)=1584
All powers of the terms are prime.
%C A000001 Factorizations :
2^3*3^3, 2^5*3^3*11^3, 2^7*3^3*11^3*43^3,
2^13*3^5*5^3*19^3*23^3*31^3*137^3
No square free solution exists. All primes are cubic at
least.
The non-primitive PPSigma-perfect numbers are obtained
from the primitive ones by multiplying by m, if m is the form : Product
p_i^2 and relatively prime to the primitive PPSigma-perfect number.
%Y A000001 A096290
%K A000001 nonn
%O A000001 1, 1
%A A000001 Yasutoshi Kohmoto (zbi74583 at boat.zero.ad.jp)
A095682 : 1PPSigma perfect number has the same property.
So, it should be rewritten.
Yasutoshi
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