|
Search: id:A132359
|
|
|
| A132359 |
|
Numbers divisible by the square of their last digit. |
|
+0
1
|
|
| 1, 11, 12, 21, 25, 31, 32, 36, 41, 51, 52, 61, 63, 64, 71, 72, 75, 81, 91, 92, 101, 111, 112, 121, 125, 128, 131, 132, 141, 144, 147, 151, 152, 153, 161, 171, 172, 175, 181, 191, 192, 201, 211, 212, 216, 221, 224, 225, 231, 232, 241, 243, 251, 252, 261, 271, 272
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Subsequences are A017281 and A053742 representing last digits 1 and 5. Generators for the subsequences representing last digits 2, 3, 4, 6, 7, 8 and 9 are, in that order, the terms 12+20i, 63+90i, 64+80i, 36+180i, 147+490i, 128+320i, 729+810i, where i=0,1,2,... - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 13 2007
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..1000
|
|
FORMULA
|
Numbers n such that fp[n / (n mod 10)] = 0.
|
|
EXAMPLE
|
147 belongs to the sequence because 147/7^2=3.
|
|
MAPLE
|
isA132359 := proc(n) local ldig ; ldig := n mod 10 ; if ldig <> 0 and n mod (ldig^2) = 0 then true ; else false ; fi ; end: for n from 1 to 400 do if isA132359(n) then printf("%d, ", n) ; fi ; od: - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 13 2007
a:=proc(n) local nn: nn:=convert(n, base, 10): if 0 < nn[1] and `mod`(n, nn[1]^2) =0 then n else end if end proc: seq(a(n), n=1..250); - Emeric Deutsch (deutsch(AT)duke.poly.edu), Nov 15 2007
|
|
MATHEMATICA
|
Select[Range[250], IntegerDigits[ # ][[ -1]] > 0 && Mod[ #, IntegerDigits[ # ][[ -1]]^2] == 0 &] - Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Nov 12 2007
|
|
CROSSREFS
|
Cf. A034709.
Sequence in context: A066686 A125887 A107478 this_sequence A131363 A089185 A098754
Adjacent sequences: A132356 A132357 A132358 this_sequence A132360 A132361 A132362
|
|
KEYWORD
|
base,easy,nonn,nice
|
|
AUTHOR
|
Jonathan Vos Post (jvospost2(AT)yahoo.com), Nov 08 2007
|
|
EXTENSIONS
|
Corrected and extended by Stefan Steinerberger (stefan.steinerberger(AT)gmail.com), Emeric Deutsch (deutsch(AT)duke.poly.edu) and R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 12 2007
|
|
|
Search completed in 0.002 seconds
|
