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%I #11 Jun 12 2013 23:47:32
%S 1,1,1,2,2,2,3,2,2,3,3,3,3,5,1,1,2,4,1,5,2,2,4,5,2,2,1,2,4,6,1,5,2,4,
%T 1,4,3,5,1,4,1,7,6,8,4,4,4,9,3,2,1,5,4,9,2,2,2,3,2,8,6,9,1,1,1,2,4,8,
%U 3,1,4,7,8,8,2,3,3,3,1,8,1,2,3,10,10
%N a(n) = Number of common trailing terms on the row n of tables A225632 and A225642.
%C The positions n, in which a(n)=1: 0, 1, 2, 14, 15, 18, 26, 30, 34, 38, 40, 50, 62, 63, 64, 69, 78, 80, ...
%C By convention, a(0)=1 as this applies also to the tables A225630 and A225640, whose columns start from zero.
%C In other words, a(n) = 1 + distance from the first common term on column n (A226055(n)) of tables A225630 and A225640 to the respective fixed point, A003418(n).
%F a(n) = A225634(n)-A225638(n) = A225644(n)-A225639(n).
%e Row 7 of A225632 is:
%e 1, 12, 84, 420;
%e Row 7 of A225642 is:
%e 7, 84, 420;
%e the last two terms (84 and 420) are common to them, thus a(7)=2.
%e Row 14 of A225632 is:
%e 1, 84, 1260, 16380, 180180, 360360;
%e Row 14 of A225642 is:
%e 14, 630, 8190, 90090, 360360;
%e they have no common term until as the last term of those rows (which is A003418(14)=360360), thus a(14)=1.
%o (Scheme):
%o (define (A226056 n) (- (A225634 n) (A225638 n)))
%o (define (A226056 n) (- (A225644 n) (A225639 n))) ;; Alternative definition.
%Y Cf. A226055, A225634, A225644, A225638, A225639.
%K nonn
%O 0,4
%A _Antti Karttunen_, May 24 2013
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