%I
%S 3276,21,2,18,6,5,7,44,1,3,23,30,19,16,78,10,26,27,4,183,9,57,260,58,
%T 138,84,59,80,208,281,147,476,49,11,282,192,114,290,553,222,851,1582,
%U 1077,293,348,15,700,155,37,1234,1786,93,266,1103
%N Find smallest m such that A260409(m+1)A260409(m) = n; then a(n) = A260409(m).
%C a(71) = 8027, a(73) = 1316, a(74) = 7785, a(75) = 5407, a(80) = 9809, a(81) = 1739, a(97) = 8972 & a(98) = 9750.
%C In the first 9999 terms of the first differences of A260409, there are 2 zeros, 891 ones, 766 twos, etc.
%C These can be computed by first running the Mmca in A260310 and then Tally@ Sort @ Differences[ Transpose[ lst][[2]]]
%e a(0) = 35407 because A260409(3276) = A260409(3277) = 35407 and the difference is 0.
%e a(8) = 8 because A260409(1) = 8 and A260409(2) = 16 and the difference is 8.
%e a(9) = 18 because A260409(3) = 18 and A260409(4) = 27, which has a difference of 9.
%t (* first run the Mmca in A260310 and then *) t = Transpose[lst][[2]]; d = Differences[ Transpose[ lst][[2]]]; p = Table[ Position[d, n, 1, 1], {n, 0, 69}] // Flatten; t[[#]] & /@ p
%Y Cf. A260310, A260408, A260409.
%K nonn
%O 0,1
%A _Robert G. Wilson v_, Jul 24 2015
