A083827 Let x(n) = 123...n, y(n) = n...321; a(n) = y(n) concatenated with x(n) - x(n) concatenated with y(n).

0, 891, 197802, 30866913, 4197558024, 530864469135, 64197533580246, 7530864224691357, 864197531135802468, -135802458898641975411, -1235802366899876419763310, -2345801446790997654198553209, 77543207754310799224567922456892

Offset

1,2

Links

Table of n, a(n) for n=1..13.

Example

x(3) = 123, y(3) = 321, a(3) = 321123-123321=197802.

Mathematica

Module[{nn=20, x, y}, Table[x=Range[n]; y=Reverse[x]; FromDigits[Join[ Flatten[ IntegerDigits/@y], Flatten[IntegerDigits/@x]]]-FromDigits[ Join[ Flatten[ IntegerDigits/@x], Flatten[IntegerDigits/@y]]], {n, nn}]] (* Harvey P. Dale, Aug 02 2012 *)

Prog

(PARI) { for(n=1, 20, if(n==1, x=1; y=1; l=1; ln=1; ln=length(Str(n)); x=x*10^ln+n; y=n*10^l+y; l=l+ln; ); print((y*10^l + x) - (x*10^l + y)); ); }

Crossrefs

Sequence in context: A125303 A087672 A284842 * A268876 A068752 A173349

Adjacent sequences: A083824 A083825 A083826 * A083828 A083829 A083830

Keyword

base,easy,sign

Author

Amarnath Murthy and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 09 2003

Extensions

More terms from Ray Chandler, Jul 23 2003

Status

approved