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A072185
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Primes p = x1x2x3...xn in base 10 such that x1^p1+x2^p2+x3^p3+....+xn^pn is a prime, where pn is the n-th prime.
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0
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11, 23, 29, 41, 43, 47, 61, 67, 101, 131, 139, 151, 173, 179, 199, 263, 311, 331, 337, 359, 401, 461, 593, 601, 607, 641, 757, 809, 821, 827, 863, 881, 887, 911, 953, 977, 991, 1019, 1091, 1097, 1109, 1123, 1181, 1217, 1301, 1321, 1381, 1451, 1499, 1583
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| 23 belongs to the sequence because 2^2+3^3=31 is a prime.
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MAPLE
| Contribution from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 10 2010: (Start)
isA072185 := proc(n) local d ; if isprime(n) then d := convert(n, base, 10) ; sdg := add( op(-i, d)^ithprime(i), i=1..nops(d)) ; isprime(sdg) ; else false; end if; end proc:
for p from 2 to 2000 do if isA072185(p) then printf("%d, ", p) ; fi; end do: (End)
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PROG
| 30 for I=10 to 100000 40 L=alen(I) 50 Q=2:A=0 60 A1=val(mid(str(I), 2, 1)) 70 for H=2 to L 80 A=A+val(mid(str(I), H+1, 1))^nxtprm(Q) 90 Q=nxtprm(Q) 100 next 110 P=A+A1^2 120 if prmdiv(P)=P and P<>1 and prmdiv(I)=I and I<>1 then print I 130 next
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CROSSREFS
| Sequence in context: A086244 A091939 A166559 * A105898 A136001 A158203
Adjacent sequences: A072182 A072183 A072184 * A072186 A072187 A072188
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KEYWORD
| easy,base,nonn
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AUTHOR
| Felice Russo (frusso(AT)micron.com), Jul 01 2002
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Oct 10 2010
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