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A378796
Number of minimal edge cuts in the n-sun graph.
0
1, 6, 15, 44, 125, 370, 1099, 3288, 9849, 29534, 88583, 265732, 797173, 2391498, 7174467, 21523376, 64570097, 193710262, 581130751, 1743392220, 5230176621, 15690529826, 47071589435, 141214768264, 423644304745, 1270932914190, 3812798742519, 11438396227508, 34315188682469, 102945566047354
OFFSET
1,2
COMMENTS
The sequence has been extended to n=1 using the formula. - Andrew Howroyd, Dec 12 2024
LINKS
Eric Weisstein's World of Mathematics, Minimal Edge Cut.
Eric Weisstein's World of Mathematics, Sun Graph.
FORMULA
a(n) = (3^n + (-1)^n)/2 + n - 1 = A046717(n) + n - 1. - Andrew Howroyd, Dec 12 2024
PROG
(PARI) a(n) = (3^n + (-1)^n)/2 + n - 1 \\ Andrew Howroyd, Dec 12 2024
CROSSREFS
Sequence in context: A272320 A137806 A193449 * A197160 A182420 A117961
KEYWORD
nonn,new
AUTHOR
Eric W. Weisstein, Dec 07 2024
EXTENSIONS
a(1)-a(2) prepended and a(7) onwards from Andrew Howroyd, Dec 12 2024
STATUS
approved