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A217775
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a(n) = n*(n+1) + (n+2)*(n+3) + (n+4)*(n+5).
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2
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26, 44, 68, 98, 134, 176, 224, 278, 338, 404, 476, 554, 638, 728, 824, 926, 1034, 1148, 1268, 1394, 1526, 1664, 1808, 1958, 2114, 2276, 2444, 2618, 2798, 2984, 3176, 3374, 3578, 3788, 4004, 4226, 4454, 4688, 4928, 5174, 5426, 5684, 5948, 6218, 6494, 6776, 7064
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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0,1
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LINKS
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FORMULA
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EXAMPLE
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a(1) = 1*2 + 3*4 + 5*6 = 2 + 12 + 30 = 44.
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MAPLE
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MATHEMATICA
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Table[3n^2+15n+26, {n, 0, 50}] (* or *) LinearRecurrence[{3, -3, 1}, {26, 44, 68}, 50] (* Harvey P. Dale, Oct 09 2018 *)
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PROG
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(JavaScript)
for (j=0; j<50; j++) {
a=j*(j+1)+(j+2)*(j+3)+(j+4)*(j+5);
document.write(a+", ");
}
(Magma) [(3*(2*n+5)^2 + 29)/4: n in [0..50]]; // G. C. Greubel, Aug 27 2019
(Sage) [(3*(2*n+5)^2 + 29)/4 for n in (0..50)] # G. C. Greubel, Aug 27 2019
(GAP) List([0..50], n-> (3*(2*n+5)^2 + 29)/4 ); # G. C. Greubel, Aug 27 2019
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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