cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A017643 a(n) = (12n+10)^3.

Original entry on oeis.org

1000, 10648, 39304, 97336, 195112, 343000, 551368, 830584, 1191016, 1643032, 2197000, 2863288, 3652264, 4574296, 5639752, 6859000, 8242408, 9800344, 11543176, 13481272, 15625000, 17984728, 20570824, 23393656, 26463592, 29791000, 33386248, 37259704
Offset: 0

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6n + 5 = (12n + 10) / 2 is never a square, as 5 is not a quadratic residue modulo 6. Using this, we can show that each term has an even square part and an even squarefree part, neither part being a power of 2. (Less than 2% of integers have this property - see A339245.) - Peter Munn, Dec 14 2020

Crossrefs

A000578, A017641 are used in a formula defining this sequence.
Subsequence of A339245.

Programs

  • Maple
    A017643:=(12*n+10)^3; seq(A017643(n), n=0..100); # Wesley Ivan Hurt, Nov 25 2013
  • Mathematica
    (12Range[0,30]+10)^3 (* or *) LinearRecurrence[{4,-6,4,-1},{1000,10648,39304,97336},30] (* Harvey P. Dale, Sep 30 2011 *)

Formula

a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) with a(0)=1000, a(1)=10648, a(2)=39304, a(3)=97336. [Harvey P. Dale, Sep 30 2011]
a(n) = A017641(n)^3 = A000578(A017641(n)). - Michel Marcus, Nov 25 2013
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