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Number of partitions of 7*8^n into powers of 8, also equals column 1 of triangle A111835, which shifts columns left and up under matrix 8th power.
7

%I #11 Jun 13 2017 22:36:38

%S 1,8,232,36968,35593832,219379963496,9003699178010216,

%T 2530260913162860295784,4970141819535151534947497576,

%U 69322146154435681317709098939119208

%N Number of partitions of 7*8^n into powers of 8, also equals column 1 of triangle A111835, which shifts columns left and up under matrix 8th power.

%C Let q=8; a(n) equals the partitions of (q-1)*q^n into powers of q, or, the coefficient of x^((q-1)*q^n) in 1/Product_{j>=0}(1-x^(q^j)).

%H Alois P. Heinz, <a href="/A111836/b111836.txt">Table of n, a(n) for n = 0..40</a>

%F a(n) = [x^(7*8^n)] 1/Product_{j>=0}(1-x^(8^j)).

%o (PARI) a(n,q=8)=local(A=Mat(1),B);if(n<0,0, for(m=1,n+2,B=matrix(m,m);for(i=1,m, for(j=1,i, if(j==i || j==1,B[i,j]=1,B[i,j]=(A^q)[i-1,j-1]);));A=B); return(A[n+2,2]))

%Y Cf. A111835 (triangle), A002577 (q=2), A078124 (q=3), A111817 (q=4), A111821 (q=5), A111826 (q=6), A111831 (q=7).

%K nonn

%O 0,2

%A _Gottfried Helms_ and _Paul D. Hanna_, Aug 22 2005