|
Search: id:A113572
|
|
|
| A113572 |
|
Least n digit multiple of n such that the r-th digit is prime if r is a prime else it is composite. The location and value of the most significant digit is 1. 0 if no such number exists. |
|
+0
2
|
|
| 1, 12, 123, 1224, 12245, 122424, 1224265, 12242424, 122424246
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
Conjecture: No term is zero.
|
|
EXAMPLE
|
a(6) = 122424, the first digit is 1, the 2nd, 3rd and the 5th digits are primes and the 4th and 6th digit are composite.
|
|
CROSSREFS
|
Cf. A113573.
Adjacent sequences: A113569 A113570 A113571 this_sequence A113573 A113574 A113575
Sequence in context: A078189 A127422 A079847 this_sequence A037701 A037610 A035239
|
|
KEYWORD
|
base,easy,more,nonn
|
|
AUTHOR
|
Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 06 2005
|
|
EXTENSIONS
|
Corrected and extended by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 29 2007
|
|
|
Search completed in 0.002 seconds
|
