|
Search: id:A007942
|
|
|
| A007942 |
|
Concatenation of sequence (n,n-1,..,2,1,2,..,n-1,n). |
|
+0
2
|
|
| 1, 212, 32123, 4321234, 543212345, 65432123456, 7654321234567, 876543212345678, 98765432123456789, 109876543212345678910, 1110987654321234567891011
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Also called Smarandache mirror sequence.
|
|
REFERENCES
|
F. Smarandache, "Only Problems, not Solutions!", Xiquan Publ., Phoenix-Chicago, 1993
|
|
LINKS
|
M. L. Perez et al., eds., Smarandache Notions Journal
F. Smarandache, Only Problems, Not Solutions!
|
|
FORMULA
|
a(n+1)=n*10^{floor[1+log10(a(n))]+floor[1+log10(n)]}+a(n)*10^floor[1+log10(n)]+n, with a(1)=1 - Paolo P. Lava (ppl(AT)spl.at), Jun 04 2008
|
|
MAPLE
|
P:=proc(n) local a, b, i; a:=1; b:=0; print(a); for i from 1 by 1 to n do b:=a; a:=(i+1)*10^(2+floor(evalf(log10(b), 10))+floor(evalf(log10(i+1), 10)))+b*10^(1+floor(evalf(log10(i+1), 10)))+i+1; print(a); od; end: P(100); - Paolo P. Lava (ppl(AT)spl.at), Jun 04 2008
|
|
CROSSREFS
|
Adjacent sequences: A007939 A007940 A007941 this_sequence A007943 A007944 A007945
Sequence in context: A114880 A082828 A083962 this_sequence A079794 A138568 A092126
|
|
KEYWORD
|
nonn,base,easy
|
|
AUTHOR
|
R. Muller
|
|
|
Search completed in 0.002 seconds
|
