

A348645


a(n) = (12*n + 1)*(5184*n^2 + 540*n + 13).


3



13, 74581, 545725, 1786693, 4170733, 8071093, 13861021, 21913765, 32602573, 46300693, 63381373, 84217861, 109183405, 138651253, 172994653, 212586853, 257801101, 309010645, 366588733, 430908613, 502343533, 581266741, 668051485, 763071013, 866698573, 979307413, 1101270781
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,1


COMMENTS

a(n) is the entry (2,1) of a family of unimodular matrices none of whose entries is 1 or 1, such that when each entry of the matrix is replaced by its cube, the resulting matrix is also unimodular.
In these matrices, the entries (1,3) and (3,1) = 2; the entries (2,3) and (3,2) = 3; the entry (3,3) = 0.


LINKS



PROG

(PARI) a(n) = (12*n + 1)*(5184*n^2 + 540*n + 13);


CROSSREFS



KEYWORD

nonn,easy


AUTHOR



STATUS

approved



