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Even terms in A247665 in order of appearance.
7

%I #18 Oct 16 2014 00:31:40

%S 2,4,8,14,16,32,64,128,122,244,256,512,866,1024,1766,2048,4006,4096,

%T 8192,8482,12242,16384,32768,52586,65536,105806,131072

%N Even terms in A247665 in order of appearance.

%C What are the terms that are not powers of 2?

%D _Amarnath Murthy_, Email to _N. J. A. Sloane_, Oct 05 2014.

%e Table (extracted from Russ Cox's extended table in A247665) showing index where even numbers appear, the even number, and the number of different prime factors of that term:

%e 3 4 1

%e 7 8 1

%e 15 14 2

%e 31 16 1

%e 63 32 1

%e 127 64 1

%e 255 128 1

%e 511 122 2

%e 1023 244 2

%e 2047 256 1

%e 4095 512 1

%e 8191 866 2

%e 16383 1024 1

%e 32767 1766 2

%e 65535 2048 1

%e 131071 4006 2

%e 262143 4096 1

%e 524287 8192 1

%e 1048575 8482 2

%e 2097151 12242 2

%e 4194303 16384 1

%e 8388607 32768 1

%e 16777215 52586 2

%e 33554431 65536 1

%e 67108863 105806 2

%e 134217727 131072 1

%e ...

%Y Cf. A247665, A248381, A248387, A248388.

%K nonn,more

%O 1,1

%A _N. J. A. Sloane_, Oct 08 2014

%E More terms from _Russ Cox_, Oct 11 2014