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A231203 Numbers of the form (24*x + 1)*2^(y+6) with positive integers x and y. 1
3200, 6272, 6400, 9344, 12416, 12544, 12800, 15488, 18560, 18688, 21632, 24704, 24832, 25088, 25600, 27776, 30848, 30976, 33920, 36992, 37120, 37376, 40064, 43136, 43264, 46208, 49280, 49408, 49664, 50176, 51200, 52352, 55424, 55552, 58496, 61568, 61696 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Let F(m) = 2^(2^m) + 1 be a Fermat number. If F(m) = (a*2^n + 1)*(b*2^n + 1) for some n >= m + 2 and a and b are odd, then a + b is in the sequence.

LINKS

Table of n, a(n) for n=1..37.

Eric Weisstein's World of Mathematics, Fermat Number

CROSSREFS

Cf. A000215.

Sequence in context: A269114 A035896 A224646 * A035777 A108001 A212074

Adjacent sequences:  A231200 A231201 A231202 * A231204 A231205 A231206

KEYWORD

nonn

AUTHOR

Arkadiusz Wesolowski, Nov 05 2013

STATUS

approved

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Last modified September 19 23:59 EDT 2019. Contains 327207 sequences. (Running on oeis4.)