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.

A095682 Primitive 1+prime power perfect numbers: if n=Product p_i^r_i then 1PPsigma(n)= Product {Sum p_i^r_i, 1<=s_i<=r_i, s_i is one or prime} 1PPsigma(n)=2*n.

Original entry on oeis.org

36, 392, 152352, 6072901632, 1444601174400
Offset: 1

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Factorizations: 2^2*3^2, 2^3*7^2, 2^5*3^2*23^2, 2^13*3^2*7^2*41^2, 2^7*3^5*5^2*29^2*47^2. No squarefree solution exists.

Examples

			1PPsigma(2^5*3^3)=(2+2^2+2^3+2^5)*(3+3^2+3^3)=1794
		

Crossrefs

Cf. A096290.