

A181178


nth zerofree positive number with digital sum n.


5



1, 11, 21, 31, 41, 51, 61, 71, 81, 118, 137, 165, 193, 257, 294, 376, 467, 567, 676, 785, 894, 1399, 1778, 1986, 2887, 3869, 4869, 5878, 6887, 7896, 8959, 9968, 18798, 26998, 35999, 45999, 56899, 66989, 76998, 87799
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OFFSET

1,2


COMMENTS

nth value in nth row of triangular array A069800 in which nth row consists of numbers (excluding the digit 0) with digit sum n arranged in increasing numerical order.
For n>376, a(n) has decimal representation xyy...y, where x = (n+1) mod 9 + 1, and among y's exactly two equal 8 and the rest equal 9. For example, a(377) = 1999999998999999999999999999999999989999999.  Max Alekseyev, Aug 20 2013


LINKS

Zak Seidov, Table of n, a(n) for n = 1..70


EXAMPLE

a(1) = 1 because 1 is the 1st number with digital sum 1;
a(2) = 11 because 11 is the 2nd number with digital sum 2 {2,11};
a(3) = 21 because 21 is the 3rd (zerofree positive) number with digital sum 3 {3,12,21,111};
a(4) = 31 because 31 is the 4th (zerofree positive) number with digital sum 4 {4,13,22,31,112,121,211,1111}.


MATHEMATICA

nn=50; c=Table[0, {nn}]; t=c; cnt=0; n=0; While[cnt<nn, n++; If[DigitCount[n, 10, 0]==0, s=Total[IntegerDigits[n]]; If[s<=nn, c[[s]]++; If[c[[s]]==s, t[[s]]=n; cnt++]]]]; t


CROSSREFS

Cf. A007953, A069800, A081927
Sequence in context: A061589 A110402 A081927 * A178205 A239464 A180105
Adjacent sequences: A181175 A181176 A181177 * A181179 A181180 A181181


KEYWORD

nonn,base,easy


AUTHOR

Jonathan Vos Post, Jan 25 2011


STATUS

approved



