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 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. 1
 6, 28, 4512, 65520, 694400 (list; graph; refs; listen; history; text; internal format)
 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 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: A097464 A166998 A038182 * A057246 A154895 A276493 Adjacent sequences:  A095720 A095721 A095722 * A095724 A095725 A095726 KEYWORD nonn AUTHOR Yasutoshi Kohmoto, Jul 08 2004 STATUS approved

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Last modified October 16 12:00 EDT 2019. Contains 328056 sequences. (Running on oeis4.)