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A123911
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Numbers n such that if you multiply the primes that are indexed by the digits of n and add the sum of digits of n you get n.
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0
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OFFSET
| 1,1
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COMMENTS
| As prime(0) is not defined, n may not contain any zero digits.
a(10) > 10^40 [From Max Alekseyev (maxale(AT)gmail.com), Feb 08 2010]
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EXAMPLE
| 2295 is in the sequence because prime(2)*prime(2)*prime(9)*prime(5) + sum of digits of 2295 = 3*3*23*11 + (2+2+9+5) = 2277 + 18 = 2295.
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MATHEMATICA
| fQ[n_] := ! MemberQ[IntegerDigits@n, 0] && Times @@ Prime@ IntegerDigits@n + Plus @@ IntegerDigits@n == n; Do[ If[fQ@n, Print@n], {n, 2*10^9}]
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PROG
| (PARI) { a(m) = forvec(v=vector(8, i, [0, m]), u=vector(9, i, if(i<9, v[i], m)-if(i>1, v[i-1], 0) ); t=prod(i=1, 9, prime(i)^u[i])+sum(i=1, 9, u[i]*i); s=eval(Vec(Str(t))); if(#s!=m, next); w=vector(9); for(j=1, #s, if(s[j], w[s[j]]++)); if(u==w, print(t)), 1) } /* m is the length */ [From Max Alekseyev (maxale(AT)gmail.com), Feb 08 2010]
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CROSSREFS
| Sequence in context: A180454 A023323 A163513 * A126173 A083572 A179699
Adjacent sequences: A123908 A123909 A123910 * A123912 A123913 A123914
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KEYWORD
| base,more,nonn
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AUTHOR
| Tanya Khovanova (tanyakh(AT)yahoo.com), Oct 28 2006
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EXTENSIONS
| a(4) and a(5) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Apr 22 2008
a(6)-a(9) from Max Alekseyev (maxale(AT)gmail.com), Feb 08 2010
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