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A062321
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a(1) = 1; a(n) = gcd {n * (n + 1), a(n-1) * (a(n-1) + 1)} for n > 1.
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1
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1, 2, 6, 2, 6, 42, 14, 6, 6, 2, 6, 6, 14, 210, 30, 2, 6, 6, 2, 6, 42, 2, 6, 6, 2, 6, 42, 14, 30, 930, 62, 6, 6, 14, 210, 6, 2, 6, 6, 2, 6, 42, 86, 6, 6, 2, 6, 42, 14, 30, 6, 2, 6, 6, 14, 42, 6, 2, 6, 6, 2, 6, 42, 2, 6, 6, 2, 6, 42, 14, 6, 6, 2, 6, 6, 14, 42, 6, 2, 6, 6, 2, 6, 42, 86, 7482
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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LINKS
| Harry J. Smith, Table of n, a(n) for n=1,...,1000
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EXAMPLE
| a(31) = gcd(31 * 32, a(30) * (a(30) + 1)) = gcd(31*32, 930*931) = 62
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MATHEMATICA
| RecurrenceTable[{a[1]==1, a[n]==GCD[n(n+1), a[n-1](a[n-1]+1)]}, a, {n, 90}] (* From Harvey P. Dale, Dec 21 2011 *)
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PROG
| (PARI) { for (n=1, 1000, if (n>1, a=gcd(n*(n + 1), a*(a + 1)), a=1); write("b062321.txt", n, " ", a) ) } [From Harry J. Smith (hjsmithh(AT)sbcglobal.net), Aug 04 2009]
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CROSSREFS
| Sequence in context: A151705 A170861 A078992 * A086356 A086359 A091944
Adjacent sequences: A062318 A062319 A062320 * A062322 A062323 A062324
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KEYWORD
| nonn
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AUTHOR
| Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Jul 05 2001
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