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A249552
Numbers m such that there are precisely 9 groups of order m.
21
308, 532, 644, 836, 868, 1316, 1364, 1652, 1748, 1815, 1876, 1892, 2068, 2212, 2324, 2356, 2596, 2852, 2884, 2996, 3124, 3268, 3476, 3572, 3652, 3668, 3892, 3956, 4228, 4263, 4484, 4532, 4564, 4676, 4708, 5012, 5092, 5332, 5348, 5396, 5428, 5572, 5588, 5764, 5828, 6004, 6116, 6164, 6244, 6308, 6356, 6532
OFFSET
1,1
MAPLE
select(t -> GroupTheory:-NumAbelianGroups(t) <= 9 and GroupTheory:-NumGroups(t) = 9, [$1..10000]); # Robert Israel, Mar 26 2018
PROG
(GAP) A249552:=Filtered([1..2015], n->NumberSmallGroups(n)=9); # Muniru A Asiru, Nov 17 2017
CROSSREFS
Cf. A000001. Cyclic numbers A003277. Numbers m such that there are precisely k groups of order m: A054395 (k=2), A055561 (k=3), A054396 (k=4), A054397 (k=5), A135850 (k=6), A249550 (k=7), A249551 (k=8), this sequence (k=9), A249553 (k=10), A249554 (k=11), A249555 (k=12), A292896 (k=13), A294155 (k=14), A294156 (k=15), A295161 (k=16), A294949 (k=17), A298909 (k=18), A298910 (k=19), A298911 (k=20).
Sequence in context: A309566 A118843 A224675 * A237457 A234211 A053172
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 01 2014
EXTENSIONS
a(13)-a(16) from Muniru A Asiru, Oct 21 2017
More terms from Muniru A Asiru, Oct 23 2017
More terms from Muniru A Asiru, Nov 17 2017
Incorrect b-file shortened by Jorge R. F. F. Lopes, Jan 07 2022
STATUS
approved