login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A116345 Numbers n such that n times n+6 gives the concatenation of two numbers m and m+8. 6
41, 54, 40354308, 59645687, 39704957106129738595969799927611, 44505281604832422780051712184760, 45053875613995255103944518907120, 54946124386004744896055481092875, 55494718395167577219948287815235, 60295042893870261404030200072384, 68683652917306421895276391964227 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..41

EXAMPLE

59645687 * 59645693 = 35576083//35576091, where // denotes concatenation.

MAPLE

f:= proc(d) local R;

   R:= map(rhs@op, {msolve(x^2=17, 10^d+1)});

   R:= map(t -> (t-3) mod (10^d+1), R);

   op(select(proc(t) local m; m:= (t*(t+6)-8)/(10^d+1)+8; m >= 10^(d-1) and m < 10^d end proc, R));

end proc;

sort(convert({seq(f(i), i=1..50)}, list)); # Robert Israel, Jan 17 2017

CROSSREFS

Cf. A116168, A116339, A116344, A116346, A116352.

Sequence in context: A115663 A282353 A118636 * A127333 A262722 A172406

Adjacent sequences:  A116342 A116343 A116344 * A116346 A116347 A116348

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, Feb 06 2006

EXTENSIONS

More terms from Robert Israel, Jan 17 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 10 11:12 EDT 2020. Contains 336379 sequences. (Running on oeis4.)