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Digits 9 to 0 are written in order with increasing number of digits for each member of the sequence. Leading zeros are counted, but are not written down.
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%I #9 Jan 17 2017 09:05:14

%S 9,87,654,3210,98765,432109,8765432,10987654,321098765,4321098765,

%T 43210987654,321098765432,1098765432109,87654321098765,

%U 432109876543210,9876543210987654,32109876543210987,654321098765432109

%N Digits 9 to 0 are written in order with increasing number of digits for each member of the sequence. Leading zeros are counted, but are not written down.

%C This is similar to A062273 and A007923

%D C. Ashbacher, "Some problems concerning the Smarandache deconstructive sequence", Journal of Recreational Mathematics, vol. 29(2), 82-84 (1998)

%D Russell Euler and Jawad Sadek, "Some divisibility patterns in the Smarandache deconstructive sequence", Journal of Recreational Mathematics, vol. 31(1), 12-14 (2002-2003)

%e The first number in the sequence is 9.

%e The second number in the sequence is 87.

%e The third number in the sequence is 654.

%t With[{c=PadRight[{},250,Range[9,0,-1]]},Table[FromDigits[Take[c,{(n(n+1))/2+1,((n+1)(n+2))/2}]],{n,0,20}]] (* _Harvey P. Dale_, Jan 17 2017 *)

%Y Cf. A007923, A062273.

%K nonn,easy,base

%O 1,1

%A _Parthasarathy Nambi_, Jan 05 2005

%E More terms from _Robert G. Wilson v_ and _Lior Manor_, Jan 14 2005