A121189 -id:A121189 - cp's OEIS frontend

0, 0, 0, 1, 1, 5, 6, 26, 32, 133, 176, 708, 952, 3861, 5302, 21604, 29960

Offset: 1

N. J. A. Sloane, Aug 17 2006

Appears to be A047774 without every third term (all omitted terms are zeros). - Andrey Zabolotskiy, Jul 29 2023

S. J. Cyvin, Jianji Wang, J. Brunvoll, Shiming Cao, Ying Li, B. N. Cyvin, and Yugang Wang, Staggered conformers of alkanes: complete solution of the enumeration problem, J. Molec. Struct. 413-414 (1997), 227-239. See Table 5, column C_2.

Cf. other columns of Cyvin et al.'s Table 5: A027610 (spectral isomers), A007173 (stereoisomers), A047775 (C_s), A047772 (C_i), A047774 (C_3, apparently), A047767 (C_{2h}), A047761 (C_{2v}), A047773 (C_{3v}, apparently).

0, 0, 1, 2, 13, 19, 87, 128, 529, 739, 3012

Offset: 4

N. J. A. Sloane, Aug 17 2006

S. J. Cyvin, B. N. Cyvin, J. Brunvoll, and J. Wang, Enumeration of staggered conformers of alkanes and monocyclic cycloalkanes, J. Molec. Struct., 445 (1998), 127-137. See Table 3, branched, column C_2.
S. J. Cyvin, Jianji Wang, J. Brunvoll, Shiming Cao, Ying Li, B. N. Cyvin, and Yugang Wang, Staggered conformers of alkanes: complete solution of the enumeration problem, J. Molec. Struct. 413-414 (1997), 227-239. See Table 6, branched, column C_2.

Cf. columns of Table 6 from Cyvin et al. (1997) and Table 3 of Cyvin et al. (1998), in pairs (branched, unbranched): this sequence and A121189 (C_2), A121182 and A121190 (C_s), A121183 and A121184 (C_1), A121191 and A121192 (C_i), A121185 and A121186 (spectral isomers), A121187 and A121188 (stereoisomers).

cp's OEIS Frontend