A343956 a(n) is the number of pentagonal faces of Johnson solid J_n.

0, 1, 0, 0, 1, 6, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 0, 0, 1, 6, 0, 0, 0, 0, 2, 2, 7, 7, 12, 0, 0, 0, 2, 2, 7, 7, 12, 12, 0, 0, 2, 7, 12, 0, 0, 0, 2, 2, 0, 0, 0, 0, 11, 10, 10, 9, 2, 3, 3, 0, 0, 0, 1, 2, 2, 3, 12, 12, 12, 12, 11, 11, 11, 11, 10, 10, 10, 9, 0, 0, 0, 0, 0, 0, 0, 4, 3

Offset

1,6

Links

Table of n, a(n) for n=1..92.

Eric Weisstein's World of Mathematics, Johnson Solid.

Wikipedia, List of Johnson solids.

Formula

a(n) < A242731(n).

Mathematica

Array[Count[Map[Length, PolyhedronData["J" <> ToString[#], "FaceIndices"]], 5] &, 92] (* Paolo Xausa, Apr 16 2026 *)

Crossrefs

Cf. A242731, A343954, A343955, A343957, A343958, A343959.

Essentially column k = 5 of A394912.

Sequence in context: A365989 A365990 A354883 * A324878 A324398 A171916

Adjacent sequences: A343953 A343954 A343955 * A343957 A343958 A343959

Keyword

nonn,fini,full

Author

Felix Fröhlich, May 05 2021

Extensions

a(82)-a(92) from Pontus von Brömssen, May 27 2025

Status

approved