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A064159
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Numbers n such that g(n) + sopf(n) = n, where g(n)= number of nonprimes <=n [A062298] and sopf(n) = sum of primes dividing n (with repetition) [A001414].
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0
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1, 24, 27, 30, 55, 65, 95, 145, 155, 185, 205, 822, 894, 2779, 2863, 8104, 64270, 174691, 174779, 1301989, 1302457
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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MAPLE
| with (numtheory):
a:= proc(n) option remember; local k;
for k from 1+ `if`(n=1, 0, a(n-1))
while add(i[1]*i[2], i=ifactors(k)[2])<>pi(k) do od; k
end:
seq (a(n), n=1..17); # Alois P. Heinz, Dec 18 2011
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PROG
| (PARI) g(n) = s=0; for(x=1, n, if(isprime(x), n++, s++)); s sopf(n, s, fac, i) = fac=factor(n); for(i=1, matsize(fac)[1], s=s+fac[i, 1]*fac[i, 2]); return(s); for(n=1, 10^6, if(g(n)+sopf(n)==n, print(n)))
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CROSSREFS
| Sequence in context: A058627 A116203 A071833 * A141632 A141634 A162465
Adjacent sequences: A064156 A064157 A064158 * A064160 A064161 A064162
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KEYWORD
| more,nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Sep 15 2001
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EXTENSIONS
| a(17)-a(21) from Alois P. Heinz (heinz(AT)hs-heilbronn.de), Dec 18 2011
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