|
Search: id:A092911
|
|
|
| A092911 |
|
Numbers all whose divisors can be formed using their digits. Divisor digits are a subset of the digits of the number. |
|
+0
2
|
|
| 1, 11, 13, 17, 19, 31, 41, 61, 71, 101, 103, 107, 109, 113, 121, 125, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 241, 251, 271, 281, 311, 313, 317, 331, 401, 419, 421, 431, 461, 491, 521, 541, 571
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
All primes containing 1 are members.
Sequence is a subset of A011531. The first nonprime members of the sequence are 1, 121, 125, 1207, 1255, 1379, 10201, 10379, 11009, 11209, 12419, 12709, 12755,... - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 26 2007
|
|
EXAMPLE
|
131 is a member. 143 is not a member as the divisor 11 contains two ones.
|
|
MAPLE
|
isA092911 := proc(n) local digs, digsleft, divs, d, i, j ; digs := convert(n, base, 10) ; divs := numtheory[divisors](n) ; for i from 1 to nops(divs) do digsleft := digs ; d := convert(op(i, divs), base, 10) ; for j in d do if member(j, digsleft, 'jposit') then digsleft := subsop(jposit=NULL, digsleft) ; else RETURN(false) ; fi ; od ; od ; RETURN(true) ; end: for n from 1 to 600 do if isA092911(n) then printf("%d, ", n) ; fi ; od ; - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 26 2007
|
|
CROSSREFS
|
Cf. A062634, A092912.
Adjacent sequences: A092908 A092909 A092910 this_sequence A092912 A092913 A092914
Sequence in context: A045798 A003626 A092912 this_sequence A062634 A106101 A032590
|
|
KEYWORD
|
base,nonn
|
|
AUTHOR
|
Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Mar 14 2004
|
|
EXTENSIONS
|
Corrected and extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 26 2007
|
|
|
Search completed in 0.002 seconds
|
