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A101854
a(n) = n*(n+1)*(n^2 + 21*n + 50)/24.
3
6, 24, 61, 125, 225, 371, 574, 846, 1200, 1650, 2211, 2899, 3731, 4725, 5900, 7276, 8874, 10716, 12825, 15225, 17941, 20999, 24426, 28250, 32500, 37206, 42399, 48111, 54375, 61225, 68696, 76824, 85646, 95200, 105525, 116661, 128649, 141531, 155350
OFFSET
1,1
COMMENTS
5th partial summation within series as series accumulate n times from an initial sequence of Euler Triangle's row 3: 1,4,1.
FORMULA
G.f.: x*(6 - 6*x + x^2)/(1-x)^5. - Maksym Voznyy (voznyy(AT)mail.ru), Aug 11 2009; checked and corrected by R. J. Mathar, Sep 16 2009
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5), n > 5. - Harvey P. Dale, Nov 05 2011
E.g.f.: exp(x)*x*(144 + 144*x + 28*x^2 + x^3)/24. - Stefano Spezia, Oct 14 2022
MATHEMATICA
Table[25 n/12+(71n^2)/24+(11n^3)/12+n^4/24, {n, 40}] (* or *) LinearRecurrence[{5, -10, 10, -5, 1}, {6, 24, 61, 125, 225}, 40] (* Harvey P. Dale, Nov 05 2011 *)
CROSSREFS
5th row of the array shown in A101853.
Partial sums of A101853.
Sequence in context: A371046 A371019 A370985 * A273358 A325517 A344508
KEYWORD
easy,nonn
AUTHOR
Cecilia Rossiter (cecilia(AT)noticingnumbers.net), Dec 18 2004
EXTENSIONS
Formula moved to be the definition by Eric M. Schmidt, Dec 12 2013
STATUS
approved