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Search: id:A145830
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| A145830 |
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Indices for which A145768 (XOR of squares of the numbers 1...n) is a power of 2. |
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+0
3
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OFFSET
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1,2
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COMMENT
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Next term is > 10^7.
a(7) > 1.5*10^9. [From Jon E. Schoenfield (jonscho(AT)hiwaay.net), Jan 14 2009]
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PROGRAM
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(PARI) an=0; for( i=1, 10^6, an=bitxor(an, i^2); an & an==1<<valuation(a, 2) & print1(i", "))
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CROSSREFS
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A145830 = A145768 intersect A000079. A145768(a(n)) = 2^A145831(n); See also A145827-A145829.
Sequence in context: A158891 A087680 A020691 this_sequence A140364 A022321 A116484
Adjacent sequences: A145827 A145828 A145829 this_sequence A145831 A145832 A145833
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KEYWORD
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more,nice,nonn
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AUTHOR
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M. F. Hasler (MHasler(AT)univ-ag.fr), Oct 20 2008
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