cp's OEIS Frontend

A225992 Number of pairs of orthogonal (-3,4) vectors of length 7*n.

%I A225992 #7 Sep 06 2013 02:05:02
%S A225992 420,8168160,106322711040,1496349265582080,22046445329510891520,
%T A225992 329200486775643608186880,4991630444756812041482665984,
%U A225992 76438688358604087005593563299840,1179634366672136518672486151133069312
%N A225992 Number of pairs of orthogonal (-3,4) vectors of length 7*n.
%C A225992 Row 6 of A225987.
%H A225992 R. H. Hardin, <a href="/A225992/b225992.txt">Table of n, a(n) for n = 1..64</a>
%e A225992 Some solutions for n=1
%e A225992 .-3..4...-3..4...-3..4...-3..4....4..4...-3..4....4..4...-3.-3...-3.-3....4..4
%e A225992 .-3..4....4..4...-3.-3....4..4...-3..4....4.-3...-3..4...-3.-3...-3.-3....4..4
%e A225992 .-3..4....4.-3...-3.-3....4..4....4..4....4..4....4..4...-3..4...-3..4...-3..4
%e A225992 ..4..4....4..4...-3..4...-3..4...-3..4....4.-3...-3..4...-3..4...-3..4....4.-3
%e A225992 ..4.-3....4.-3...-3.-3....4.-3....4.-3...-3..4....4..4....4.-3...-3.-3...-3..4
%e A225992 ..4..4...-3..4...-3.-3....4..4....4..4....4..4....4.-3...-3.-3...-3.-3....4..4
%e A225992 ..4..4....4..4...-3..4...-3..4....4.-3....4..4...-3..4...-3.-3...-3..4....4.-3
%K A225992 nonn
%O A225992 1,1
%A A225992 _R. H. Hardin_, May 22 2013