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%I #7 May 13 2014 07:35:50
%S 45,63,72,81,90,99,108,117,126,135,144,153,162,171,180,189,198,207,
%T 216,225,234,252,261,432,441,486,495,504,549,576,594,603,612,666,675,
%U 684,702,711,720,738,756,783,810,819,828,846,873,891,927,963,972,1035,1044,1080,1260,1323,1368,1377
%N Numbers that can be written as a sum of numbers using all nonzero decimal digits in descending order and also all nonzero decimal digits in ascending order.
%C a(n) = {A242226} intersection {A242263}. The sequence is divisible by 9 and contains 58 terms.
%e 666 = 1+2+3+4+567+89 = 9+87+6+543+21.
%p g:= proc(i, j, t) option remember; `if`(i=j, {`if`(t=1, i, 10-i)},
%p {parse(cat(seq(`if`(t=1, h, 10-h), h=i..j))), seq(seq(
%p seq(x+y, y=g(h+1, j, t)), x=g(i, h, t)), h=i..j-1)})
%p end:
%p sort([(g(1, 9, 1) intersect g(1, 9, 0))[]])[]; # _Alois P. Heinz_, May 09 2014
%Y Cf. A008591, A242226, A242263.
%K nonn,base,fini,full
%O 1,1
%A _Michel Lagneau_, May 09 2014