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A085743 a(n) = T(n^3) - T(n^2), where T() are the triangular numbers (A000217). 1
0, 0, 26, 333, 1944, 7550, 22770, 57771, 129248, 262764, 495450, 879065, 1483416, 2400138, 3746834, 5671575, 8357760, 12029336, 16956378, 23461029, 31923800, 42790230, 56577906, 73883843, 95392224, 121882500, 154237850, 193454001 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

FORMULA

a(n) = (n-1)*n^2*(n^3 + n^2 + 1)/2.

EXAMPLE

a(3) = T(3^3) - T(3^2) = T(27) - T(9) = 378 - 45 = 333.

PROG

(PARI) t(n)=n*(n+1)/2; for(n=0, 50, print1(t(n^3)-t(n^2)", "))

(MAGMA) [(n-1)*n^2*(n^3+n^2+1)/2: n in [0..40]]; // Vincenzo Librandi, Sep 14 2011

CROSSREFS

Cf. A000217.

Sequence in context: A202292 A010942 A022621 * A205494 A125438 A126919

Adjacent sequences:  A085740 A085741 A085742 * A085744 A085745 A085746

KEYWORD

nonn,easy

AUTHOR

Jon Perry, Jul 21 2003

STATUS

approved

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Last modified January 19 15:13 EST 2022. Contains 350466 sequences. (Running on oeis4.)