A231304 Recurrence a(n) = a(n-2) + n^M for M=5, starting with a(0)=0, a(1)=1.
0, 1, 32, 244, 1056, 3369, 8832, 20176, 41600, 79225, 141600, 240276, 390432, 611569, 928256, 1370944, 1976832, 2790801, 3866400, 5266900, 7066400, 9351001, 12220032, 15787344, 20182656, 25552969, 32064032, 39901876, 49274400, 60413025, 73574400, 89042176
Offset: 0
Examples
a(4) = 4^5 + 2^5 = 1056; a(5) = 5^5 + 3^5 + 1^5 = 3369.
Links
- Stanislav Sykora, Table of n, a(n) for n = 0..9999
- Stanislav Sýkora, Magnetic Resonance on OEIS, Stan's NMR Blog (Dec 31, 2014), Retrieved Nov 12, 2019.
- Index entries for linear recurrences with constant coefficients, signature (6,-14,14,0,-14,14,-6,1).
Crossrefs
Programs
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Mathematica
RecurrenceTable[{a[0]==0,a[1]==1,a[n]==a[n-2]+n^5},a,{n,30}] (* or *) LinearRecurrence[{6,-14,14,0,-14,14,-6,1},{0,1,32,244,1056,3369,8832,20176},40] (* Harvey P. Dale, Jul 22 2014 *)
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PARI
nmax=100; a = vector(nmax); a[2]=1; for(i=3, #a, a[i]=a[i-2]+(i-1)^5); print(a);
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PARI
concat(0, Vec(x*(1+26*x+66*x^2+26*x^3+x^4)/((1-x)^7*(1+x)) + O(x^50))) \\ Colin Barker, Dec 22 2015
Formula
a(n) = Sum_{k=0..floor(n/2)} (n-2k)^5.
a(0)=0, a(1)=1, a(2)=32, a(3)=244, a(4)=1056, a(5)=3369, a(6)=8832, a(7)=20176, a(n) = 6*a(n-1) - 14*a(n-2) + 14*a(n-3) - 14*a(n-5) + 14*a(n-6) - 6*a(n-7) + a(n-8). - Harvey P. Dale, Jul 22 2014
From Colin Barker, Dec 22 2015: (Start)
a(n) = (1/24)*(2*n^6 + 12*n^5 + 20*n^4 - 16*n^2 - 3*(-1)^n + 3).
G.f.: x*(1 + 26*x + 66*x^2 + 26*x^3 + x^4) / ((1-x)^7*(1+x)).
(End)
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