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Search: id:A075764
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| A075764 |
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Schroeder pseudo-primes: Composite n such that n divides the n-th Schroeder number A001003(n-1). |
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1
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| 105, 261, 301, 693, 1605, 1755, 2151, 2905, 2907, 3393, 3875, 4641, 4833, 5005, 5655, 6279, 6913, 7161, 8883, 9405, 10899, 11025, 11289, 15687, 17199, 19203, 22275, 27387, 36855, 37791, 50007, 50463, 53493, 54891, 55209, 55755, 63327, 64337
(list; graph; listen)
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OFFSET
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1,1
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EXAMPLE
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105 is a member because A001003(105) = 15646506064359350392347086201481965698808674470977505246623827696393838448345 which is divisible by 105.
105 is a member because A001003(104) = 15646506064359350392347086201481965698808674470977505246623827696393838448345 which is divisible by 105.
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PROGRAM
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(PARI) x1 = 1; x2 = 1; for (n = 3, 100000, x = (3*(2*n - 3)*x1 - (n - 3)*x2)/n; if (!isprime(n), if (!(x%n), print(n))); x2 = x1; x1 = x); (Wasserman)
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CROSSREFS
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Cf. A001003, A013998, A075762.
Sequence in context: A069692 A088595 A146257 this_sequence A046299 A010090 A147576
Adjacent sequences: A075761 A075762 A075763 this_sequence A075765 A075766 A075767
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KEYWORD
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easy,nonn
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AUTHOR
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Benoit Cloitre (benoit7848c(AT)orange.fr), Oct 09 2002
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EXTENSIONS
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More terms from David Wasserman (wasserma(AT)spawar.navy.mil), Feb 23 2005
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