A335687 (A331763(n) - A331755(n+1))/2.

4, 12, 32, 69, 121, 191, 304, 432, 582, 799, 1042, 1320, 1661, 2043, 2457, 3023, 3575, 4195, 4920, 5693, 6465, 7487, 8502, 9617, 10833, 12173, 13526, 15146, 16693, 18397, 20286, 22327, 24201, 26603, 28841, 31372, 34025, 36873, 39583, 42913, 46029

Offset: 1

Author

N. J. A. Sloane, Jul 14 2020

Keywords

• nonn

Comments

One-half of ((number of vertices in graph SC(n,2)) - (number of vertices in graph SC(n,1))).

It would be nice to have a formula for this sequence. The graphs SC(n,1) are fairly well understood, while SC(n,m) is basically a mystery for m >= 2.

Note that the offsets in A331755 and A331763 have different meanings, which is why there is an extra "+1" in the definition of the current sequence.

Examples

			For n=2, SC(2,2) has 37 vertices and SC(2,1) has 13 vertices (see illustrations), so a(2) = (37-13)/2 = 12.
		

Links

• N. J. A. Sloane, Table of n, a(n) for n = 1..100
• Scott R. Shannon, Colored illustration for the graph SC(2,1)
• Scott R. Shannon, Colored illustration for the graph SC(2,2)

Crossrefs

Cf. A331452, A331755, A331763.