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A231701
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Numbers > 100 with decimal digits in arithmetic progression mod 10.
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1
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109, 111, 123, 135, 147, 159, 161, 173, 185, 197, 208, 210, 222, 234, 246, 258, 260, 272, 284, 296, 307, 319, 321, 333, 345, 357, 369, 371, 383, 395, 406, 418, 420, 432, 444, 456, 468, 470, 482, 494, 505, 517, 529, 531, 543, 555, 567, 579, 581, 593, 604, 616
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OFFSET
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1,1
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COMMENTS
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This sequence contains straight-line numbers > 99 (A135643).
Each set of numbers from 10^n to 10^(n+1) contains 90 of these numbers. - T. D. Noe, Nov 12 2013
The sequence mod 100 has period 900, the sequence mod 90 has period 8100. - Paul Tek, Nov 14 2013
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LINKS
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Paul Tek, Table of n, a(n) for n = 1..1000
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EXAMPLE
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(8,2,6,0,4,...) is an arithmetic progression mod 10, hence the number 82604 appears in this sequence.
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MATHEMATICA
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Select[Range[100, 10^3], Length[Union[Mod[Differences[IntegerDigits[#]], 10]]] <= 1 &] (* T. D. Noe, Nov 12 2013 *)
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PROG
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(PARI) a(n) = my(len=3+(n-1)\90, \
fs=10+((n-1)%90), \
f=fs\10, \
s=fs%10); \
return(sum(i=1, len, 10^(len-i)*((f+(i-1)*(s-f))%10)))
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CROSSREFS
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Cf. A135643, A231588.
Sequence in context: A253431 A253438 A263194 * A051046 A196667 A196673
Adjacent sequences: A231698 A231699 A231700 * A231702 A231703 A231704
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KEYWORD
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nonn,base
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AUTHOR
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Paul Tek, Nov 12 2013
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STATUS
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approved
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