A152246 Composites c where |c-m| = 1, where m is any of the smallest positive integers with their number of divisors. (m belongs to sequence A007416.)
15, 25, 35, 49, 63, 65, 119, 121, 143, 145, 361, 575, 721, 841, 899, 901, 959, 961, 1023, 1025, 1261, 1295, 1679, 1681, 2519, 2881, 3071, 3073, 3599, 3601, 4095, 4097, 5041, 5183, 5185, 6479, 6721, 9215, 9217, 10081, 12287, 14399, 15119, 20159, 25199
Offset: 1
Keywords
Examples
The smallest positive integer with 8 divisors is 24. 24 - 1 = 23 is prime. But 24 + 1 = 25 is composite. So 25 is in the sequence, while 23 is not.
Extensions
Extended by Ray Chandler, Dec 05 2008