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A154561
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Primes of the form sum of digits of n + sum of digits of prime(n).
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0
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3, 5, 11, 7, 13, 17, 23, 13, 23, 23, 13, 17, 23, 29, 19, 17, 29, 23, 17, 19, 23, 29, 23, 19, 31, 23, 17, 19, 29, 31, 31, 23, 11, 19, 19, 17, 19, 23, 17, 17, 17, 23, 29, 31, 23, 29, 23, 13, 19, 19, 31, 23, 23, 17, 11, 31, 23, 13, 23, 29, 23, 29, 29, 19, 23, 31, 37, 29, 37, 17
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| If n=1 and prime=2, then 1+2=3(prime)=a(1). If n=2 and prime=3, then 2+3=5(prime)=a(2). If n=3 and prime=5, then 3+5=8=composite. If n=4 and prime=7, then 4+7=11(prime)=a(3). If n=5 and prime=11, then 5+1+1=7(prime)=a(4), etc.
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MAPLE
| Contribution from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 05 2010: (Start)
A007953 := proc(n) add(d, d=convert(n, base, 10)) ; end proc:
for n from 1 to 300 do a := A007953(n) +A007953(ithprime(n)) ; if isprime(a) then printf("%d, ", a ) ; end if; end do: (End)
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CROSSREFS
| Cf. A000040.
Sequence in context: A046228 A132162 A168323 * A073653 A145398 A087322
Adjacent sequences: A154558 A154559 A154560 * A154562 A154563 A154564
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KEYWORD
| nonn,base
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AUTHOR
| Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Jan 12 2009
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EXTENSIONS
| Corrected from a(35) onwards by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), May 05 2010
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