A069875 Smallest multiple of n with a prime signature different from all previous terms.

1, 2, 6, 4, 20, 24, 42, 8, 36, 60, 176, 72, 312, 210, 180, 16, 544, 144, 912, 320, 420, 792, 2208, 216, 800, 1560, 243, 896, 4176, 900, 5580, 64, 2112, 3570, 1680, 432, 7992, 4864, 3744, 1600, 14760, 2688, 18060, 4752, 1800, 11040, 24064, 864, 6272, 3600

Offset

1,2

Links

Table of n, a(n) for n=1..50.

Example

a(1) through a(4) have prime signatures 0, 1, (1, 1) and 2. a(5) = 20 because 5 has prime signature 1, which has already been used and 10 and 15 have prime signature (1, 1), which has already been used, but 20 has prime signature (2, 1), which has not yet been used.

Crossrefs

Sequence in context: A309243 A112326 A075435 * A202962 A019088 A096085

Adjacent sequences: A069872 A069873 A069874 * A069876 A069877 A069878

Keyword

nonn

Author

Amarnath Murthy, Apr 25 2002

Extensions

More terms from David Wasserman, Apr 30 2003

Status

approved