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Convolution of A008619 and A001400.
3

%I #12 Feb 17 2016 09:48:32

%S 1,2,5,9,17,27,44,65,97,136,191,257,346,451,587,746,946,1177,1461,

%T 1786,2178,2623,3151,3746,4443,5223,6126,7131,8283,9558,11007,12603,

%U 14403,16377,18588,21003,23692,26618,29858,33372,37244,41430,46022,50972

%N Convolution of A008619 and A001400.

%C This is row 21 of a table of values related to Molien series. It is the product of the sequence on row 3 (A008619) with the sequence on row 7 (A001400).

%C This table may be constructed by moving the rows of table A008284 to prime locations and generating the composite locations by multiplication in a manner similar to the calculation illustrated in the present sequence.

%C Rows 1 thru 20 and 22 thru 25 are as follows:

%C A000012 A008619 A000027 A001399 A002620 A001400 A000217 A006918 A000601 A001401 A002623 A001402 A002621 A097701 A000292 A008630 A002624 A008631 A057524 A002622 A008632 A001752 A117485.

%H Alois P. Heinz, <a href="/A139672/b139672.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Rec#order_13">Index entries for linear recurrences with constant coefficients</a>, signature (2, 1, -3, 0, -1, 2, 2, -1, 0, -3, 1, 2, -1).

%F G.f.: x/((x^2+x+1)*(x^2+1)*(x+1)^3*(x-1)^6). - _Alois P. Heinz_, Nov 10 2008

%F a(n)= -A049347(n)/27 +(2*n+11)*(6*n^4+132*n^3+914*n^2+2068*n+1055)/69120 -(-1)^n*(51/512+n^2/256+11*n/256+A057077(n)/32 ). - _R. J. Mathar_, Nov 21 2008

%p a:= proc(n) local m, r; m:= iquo (n, 12, 'r'); r:= r+1; (19+ (145+ (260+ 15* (r+9)*r+ (405+ 90*r+ 216*m) *m) *m) *m) *m/5+ [0, 1, 2, 5, 9, 17, 27, 44, 65, 97, 136, 191][r]+ [0, 16, 37, 77, 128, 208, 307, 447, 616, 840, 1105, 1441][r]*m/2+ [0, 52, 119, 213, 328, 476, 651, 865, 1112, 1404, 1735, 2117][r]*m^2/2 end: seq (a(n), n=1..50); # _Alois P. Heinz_, Nov 10 2008

%t CoefficientList[Series[x/((x^2+x+1)(x^2+1)(x+1)^3 (x-1)^6),{x,0,50}],x] (* or *) LinearRecurrence[{2,1,-3,0,-1,2,2,-1,0,-3,1,2,-1},{0,1,2,5,9,17,27,44,65,97,136,191,257},50] (* _Harvey P. Dale_, Feb 17 2016 *)

%K nonn

%O 1,2

%A _Alford Arnold_, Apr 29 2008, May 01 2008

%E More terms from _Alois P. Heinz_, Nov 10 2008

%E Corrected A-number in definition. Added formula. - _R. J. Mathar_, Nov 21 2008