A095723 0+1+Prime power perfect numbers: if n=Product p_i^r_i then 01PPsigma(n)= Product {Sum p_i^r_i, 0<=s_i<=r_i, s_i is 0 or one or prime} 01PPsigma(n)=2*n.

6, 28, 4512, 65520, 694400

Offset

1,1

Comments

Factorizations : 2*3, 2^2*7, 2^5*3*47, 2^4*3^2*5*7*13, 2^7*5^2*7*31

No other terms < 3000000000. - Jud McCranie, Jul 16 2004

Links

Table of n, a(n) for n=1..5.

Example

01PPsigma(2^5*3^3)=(1+2+2^2+2^3+2^5)*(1+3+3^2+3^3)=1880
All exponents of the terms are 0 or 1 or prime.

Crossrefs

Cf. A096290, A095724.

Sequence in context: A354072 A166998 A038182 * A057246 A154895 A330163

Adjacent sequences: A095720 A095721 A095722 * A095724 A095725 A095726

Keyword

nonn

Author

Yasutoshi Kohmoto, Jul 08 2004

Status

approved