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A108608 5-almost primes whose sum of factors is a prime. 3

%I

%S 48,80,108,176,252,300,368,405,420,464,468,500,567,660,675,684,848,

%T 891,944,980,1020,1116,1136,1140,1323,1332,1377,1424,1428,1452,1539,

%U 1548,1575,1616,1700,1716,1740,1820,1860,1875,1932,2096,2156,2196,2295,2300

%N 5-almost primes whose sum of factors is a prime.

%H Charles R Greathouse IV, <a href="/A108608/b108608.txt">Table of n, a(n) for n = 1..10000</a>

%e 48=2*2*2*2*3 (5-almost prime) and 2+2+2+2+3=11 is a prime.

%o (PARI) is(n)=my(f=factor(n));sum(i=1,#f~,f[i,2])==5 && isprime(sum(i=1,#f~,f[i,1]*f[i,2])) \\ _Charles R Greathouse IV_, Oct 11 2013

%Y Cf. A107707, A108607, A108609 (resp.) 3, 4, 6 (resp.)-almost primes whose sum of factors is a prime.

%K nonn

%O 1,1

%A _Zak Seidov_, Jun 12 2005

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Last modified November 13 02:59 EST 2019. Contains 329085 sequences. (Running on oeis4.)