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A132850
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a(0)=1. a(n) = the smallest prime dividing (n+a(n-1)), for n>=1.
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0
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1, 2, 2, 5, 3, 2, 2, 3, 11, 2, 2, 13, 5, 2, 2, 17, 3, 2, 2, 3, 23, 2, 2, 5, 29, 2, 2, 29, 3, 2, 2, 3, 5, 2, 2, 37, 73, 2, 2, 41, 3, 2, 2, 3, 47, 2, 2, 7, 5, 2, 2, 53, 3, 2, 2, 3, 59, 2, 2, 61, 11, 2, 2, 5, 3, 2, 2, 3, 71, 2, 2, 73, 5, 2, 2, 7, 83, 2, 2, 3, 83, 2, 2, 5, 89, 2, 2, 89, 3, 2, 2, 3, 5, 2, 2
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| a(4n+1) = a(4n+2) = 2, for all n >= 0. a(4n) and a(4n+3) are odd primes, for all n >= 0.
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EXAMPLE
| a(8) + 9 = 11 + 9 = 20. The smallest prime divisor of 20 is 2. So a(9) = 2.
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MATHEMATICA
| a = {1}; Do[AppendTo[a, FactorInteger[n + a[[ -1]]][[1, 1]]], {n, 1, 100}]; a - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Nov 25 2007
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CROSSREFS
| Cf. A076561.
Sequence in context: A097891 A097611 A135376 * A076561 A132851 A146316
Adjacent sequences: A132847 A132848 A132849 * A132851 A132852 A132853
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KEYWORD
| nonn
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AUTHOR
| Leroy Quet Nov 21 2007
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EXTENSIONS
| More terms from Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Nov 25 2007
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