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A298430
Numbers n such that there are precisely 13 groups of orders n and n + 1.
3
82323, 390446, 622916, 774548, 793827, 876932
OFFSET
1,1
COMMENTS
Equivalently, lower member of consecutive terms of A292896.
LINKS
H. U. Besche, B. Eick and E. A. O'Brien, A Millennium Project: Constructing Small Groups, Internat. J. Algebra and Computation, 12 (2002), 623-644.
FORMULA
Sequence is { n | A000001(n) = 13, A000001(n+1) = 13 }.
EXAMPLE
For n = 82323, A000001(82323) = A000001(82324) = 13.
For n = 390446, A000001(390446) = A000001(390447) = 13.
For n = 622916, A000001(622916) = A000001(622917) = 13.
MAPLE
with(GroupTheory): for n from 1 to 10^6 do if [NumGroups(n), NumGroups(n+1)] = [13, 13] then print(n); fi; od;
CROSSREFS
Cf. A000001. Subsequence of A292896 (Numbers n having precisely 13 groups of order n). Numbers n having precisely k groups of orders n and n+1: A295230 (k=2), A295990 (k=4), A295991 (k=5), A295992 (k=6), A295993 (k=8), A298427 (k=9), A298428 (k=10), A295994 (k=11), A298429 (k=12), this sequence (k=13), A298431 (k=14), A295995 (k=15).
Sequence in context: A204667 A288472 A162184 * A262794 A230786 A253937
KEYWORD
nonn,more
AUTHOR
Muniru A Asiru, Jan 19 2018
STATUS
approved