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Search: id:A087417
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| -1, 0, 0, 1, 2, 10, 135, 19818, 395466722, 156401766357161409, 24461512581491800525933058683030176
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OFFSET
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0,5
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COMMENT
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The sequence A058182=b(n) has the property: b(1)^3+b(2)^3+b(3)^3+...b(n)^3=b(n)*b(n+1)
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FORMULA
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a(n+1)=a(n)+A058182(n)^3, a(-n)=a(n).
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EXAMPLE
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A058182 begins 1,1,2,5,27,734,538783...=b(n)
1^3+1^3=2=a(2)=1*2=b(2)*b(3).
1^3+1^3+2^3=10=a(3)=2*5=b(3)*b(4).
1^3+1^3+2^3+5^3=135=a(4)=5*27=b(4)*b(5).
1^3+1^3+2^3+5^3+27^3=19818=a(5)=b(5)*b(6).
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PROGRAM
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(PARI) {a(n)=local(a0, a1, a2); if(n<0, a(-n), if(n<3, -(n==0), a0=a1=1; for(i=4, n, a2=a1^2+a0; a0=a1; a1=a2); a1*a0))} /* Michael Somos May 22 2005 */
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CROSSREFS
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Cf. A058182.
Sequence in context: A134051 A075199 A134981 this_sequence A091990 A014228 A059475
Adjacent sequences: A087414 A087415 A087416 this_sequence A087418 A087419 A087420
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KEYWORD
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sign
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AUTHOR
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Miklos Kristof (kristmikl(AT)freemail.hu), Oct 22 2003
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