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A241290
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The integer-valued quartic beginning: 0, 9, 0, 9, 7.
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1
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0, 9, 0, 9, 7, -100, -471, -1330, -2966, -5733, -10050, -16401, -25335, -37466, -53473, -74100, -100156, -132515, -172116, -219963, -277125, -344736, -423995, -516166, -622578, -744625, -883766, -1041525, -1219491, -1419318, -1642725, -1891496, -2167480
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OFFSET
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0,2
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COMMENTS
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At time of submission, <0, 9, 0, 9, 7> was the "smallest uninteresting number", in the sense that it was the least sequence of five decimal digits that was not retrieved when searching the encyclopedia (primarily offline using the sagemath interface "SloaneEncyclopedia").
The initial sequence <0, 9, 0, 9, 7> happens to define an integer-valued quartic:
a(n) = -65 p_4(n) + 36 p_3(n) - 18 p_2(n) + 9 p_1(n), n >= 0,
where the polynomials p_k(t) = binomial(t, k) are a basis for integer-valued polynomials.
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LINKS
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FORMULA
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a(n) = -(65/24)*n^4 + (89/4)*n^3 - (1363/24)*n^2 + (185/4)*n.
G.f.: x*(128*x^3-99*x^2+45*x-9) / (x-1)^5. - Colin Barker, Apr 19 2014
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MAPLE
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MATHEMATICA
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Table[-(65/24)*n^4 + (89/4)*n^3 - (1363/24)*n^2 + (185/4)*n, {n, 0, 50}] (* Wesley Ivan Hurt, Apr 18 2014 *)
LinearRecurrence[{5, -10, 10, -5, 1}, {0, 9, 0, 9, 7}, 50] (* Harvey P. Dale, Apr 02 2023 *)
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PROG
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(Sage) a(n) = -(65/24)*n^4 + (89/4)*n^3 - (1363/24)*n^2 + (185/4)*n
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CROSSREFS
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KEYWORD
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easy,sign
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AUTHOR
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STATUS
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approved
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