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Numbers with digits nondecreasing and their reciprocals sum to 1/(positive integer).
2

%I #12 Dec 12 2015 04:18:50

%S 1,2,3,4,5,6,7,8,9,22,36,44,66,88,236,244,333,488,666,999,2488,2666,

%T 3366,3446,4444,6999,8888,26999,28888,33999,34688,36666,44488,44666,

%U 55555,366999,368888,446999,448888,466688,666666,3999999,4688999,4888888,6666999,6668888,7777777,66999999,68888999,88888888,999999999

%N Numbers with digits nondecreasing and their reciprocals sum to 1/(positive integer).

%C Intersection of A037264 and A009994, A214949(a(n)) = 1. - _Reinhard Zumkeller_, Aug 02 2012

%e 1/3 + 1/4 + 1/6 + 1/8 + 1/8 = 1/1, so 34688 is in the sequence.

%o (Haskell)

%o a045910 n = a045910_list !! (n-1)

%o a045910_list = [x | x <- takeWhile (<= 999999999) $ a009994_list,

%o a214949 x == 1]

%o -- _Reinhard Zumkeller_, Aug 02 2012

%Y Condensation (by ordering digits) and completion of A037264.

%K fini,full,nonn,base

%O 1,2

%A _Len Smiley_