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A081589
Third row of Pascal-(1,5,1) array A081580.
10
1, 13, 61, 145, 265, 421, 613, 841, 1105, 1405, 1741, 2113, 2521, 2965, 3445, 3961, 4513, 5101, 5725, 6385, 7081, 7813, 8581, 9385, 10225, 11101, 12013, 12961, 13945, 14965, 16021, 17113, 18241, 19405, 20605, 21841, 23113, 24421, 25765, 27145
OFFSET
0,2
FORMULA
a(n) = 1-6*n+18*n^2.
G.f.: (1+5*x)^2/(1-x)^3.
MATHEMATICA
CoefficientList[Series[(1 + 5 x)^2 / (1 - x)^3, {x, 0, 40}], x] (* Vincenzo Librandi, Aug 09 2013 *)
PROG
(Magma) [1-6*n+18*n^2: n in [0..40]]; // Vincenzo Librandi, Aug 09 2013
(PARI) a(n)=18*n^2-6*n+1 \\ Charles R Greathouse IV, Jun 17 2017
CROSSREFS
Sequence in context: A140615 A086361 A119151 * A270449 A139880 A127876
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Mar 23 2003
STATUS
approved