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A111360
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Positive integers n such that the sum of the divisors of n and the n-th prime is divisible by n.
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0
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1, 2, 3, 9, 21, 129, 5663, 40087, 184971, 246901, 251737, 1610143, 3098384123, 19819945093, 21323898091
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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EXAMPLE
| The divisors of 21 are 1,3,7,21 and the 21st prime is 73. 1+3+7+21+73 = 105, which is divisible by 21.
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MATHEMATICA
| Select[Range[10^8], Mod[Prime[ # ] + Plus @@ Divisors[ # ], # ] == 0 &] (*Chandler*)
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PROG
| (PARI) { p=2; for(n=1, 100000000, if( (sigma(n)+p) % n == 0, print(n) ) ; p=nextprime(p+1) ; ) ; } - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Feb 11 2008
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CROSSREFS
| Sequence in context: A077550 A056780 A141505 * A111238 A057832 A089421
Adjacent sequences: A111357 A111358 A111359 * A111361 A111362 A111363
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KEYWORD
| more,nonn,changed
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AUTHOR
| Ray G. Opao (1260(AT)email.com), Nov 07 2005
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EXTENSIONS
| a(13)-a(15) from Donovan Johnson (donovan.johnson(AT)yahoo.com), Apr 22 2008
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