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A100814
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.
0
9, 87, 654, 3210, 98765, 432109, 8765432, 10987654, 321098765, 4321098765, 43210987654, 321098765432, 1098765432109, 87654321098765, 432109876543210, 9876543210987654, 32109876543210987, 654321098765432109
OFFSET
1,1
COMMENTS
This is similar to A062273 and A007923
REFERENCES
C. Ashbacher, "Some problems concerning the Smarandache deconstructive sequence", Journal of Recreational Mathematics, vol. 29(2), 82-84 (1998)
Russell Euler and Jawad Sadek, "Some divisibility patterns in the Smarandache deconstructive sequence", Journal of Recreational Mathematics, vol. 31(1), 12-14 (2002-2003)
EXAMPLE
The first number in the sequence is 9.
The second number in the sequence is 87.
The third number in the sequence is 654.
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A028339 A180751 A266828 * A055725 A219123 A144852
KEYWORD
nonn,easy,base
AUTHOR
Parthasarathy Nambi, Jan 05 2005
EXTENSIONS
More terms from Robert G. Wilson v and Lior Manor, Jan 14 2005
STATUS
approved