A074991 Concatenation of n, n+1, n+2 divided by 3.

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

Author

Amarnath Murthy, Aug 31 2002

Keywords

• base
• nonn

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.

Examples

			a(4) = 456/3 = 152.
		

Crossrefs

Cf. A074992.

Equals (1/3) A001703.

Programs

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 *)

Extensions

Incorrect conjecture deleted by Colin Barker, Sep 26 2013