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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.) 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..45.

EXAMPLE

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.

CROSSREFS

A007416, A152245

Sequence in context: A050693 A200046 A171133 * A069823 A133321 A031888

Adjacent sequences:  A152243 A152244 A152245 * A152247 A152248 A152249

KEYWORD

nonn

AUTHOR

Leroy Quet, Nov 30 2008

EXTENSIONS

Extended by Ray Chandler, Dec 05 2008

STATUS

approved

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Last modified July 25 03:36 EDT 2021. Contains 346282 sequences. (Running on oeis4.)