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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

%I #6 Apr 09 2014 10:16:43

%S 15,25,35,49,63,65,119,121,143,145,361,575,721,841,899,901,959,961,

%T 1023,1025,1261,1295,1679,1681,2519,2881,3071,3073,3599,3601,4095,

%U 4097,5041,5183,5185,6479,6721,9215,9217,10081,12287,14399,15119,20159,25199

%N 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.)

%e 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.

%Y A007416, A152245

%K nonn

%O 1,1

%A _Leroy Quet_, Nov 30 2008

%E Extended by _Ray Chandler_, Dec 05 2008

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Last modified May 9 04:44 EDT 2024. Contains 372341 sequences. (Running on oeis4.)