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A074991
Concatenation of n, n+1, n+2 divided by 3.
20
4, 41, 78, 115, 152, 189, 226, 263, 2970, 30337, 33704, 37071, 40438, 43805, 47172, 50539, 53906, 57273, 60640, 64007, 67374, 70741, 74108, 77475, 80842, 84209, 87576, 90943, 94310, 97677, 101044, 104411, 107778, 111145, 114512
OFFSET
0,1
COMMENTS
If all the three numbers have the same number of digits then the terms are in A.P. with a common difference that follows a pattern with increase in number of digits. E.g. for n = 1 to 7 the common difference, c.d. = 37. For n = 10 to 97 c.d. = 3367, For three digit numbers from 100 to 997 it is 333667 etc.
EXAMPLE
a(4) = 456/3 = 152.
MAPLE
read("transforms") ;
A074991 := proc(n)
digcatL([n, n+1, n+2]) ;
%/3 ;
end proc:
seq(A074991(n), n=0..50) ; # R. J. Mathar, Oct 04 2011
MATHEMATICA
f[n_] := FromDigits@ Flatten@ IntegerDigits[{n, n + 1, n + 2}]/3; Array[f, 26, 0] (* Robert G. Wilson v *)
CROSSREFS
Cf. A074992.
Equals (1/3) A001703.
Sequence in context: A296101 A002677 A119527 * A294972 A213823 A296800
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Aug 31 2002
EXTENSIONS
Incorrect conjecture deleted by Colin Barker, Sep 26 2013
STATUS
approved