A371340 Irregular triangle read by rows: T(n,k) is the number of chordless cycles of length k in the n-diagonal intersection graph, 4 <= k <= kmax.

1, 0, 2, 15, 6, 6, 25, 24, 30, 24, 15, 18, 18, 7, 14, 0, 30, 35, 49, 77, 91, 329, 483, 672, 1498, 2905, 5117, 7525, 8806, 9639, 7730, 4172, 1127, 196, 140, 42, 24, 8, 48, 72, 138, 256, 488, 624, 1032, 1504, 1824, 2000, 5032, 13896, 27320, 37584, 49820, 74952, 122952, 181568, 230662, 268072, 301392, 305504, 280120, 230784, 154752, 75008, 28556

Offset

4,3

Comments

A362537(n) = Sum_{k=4..kmax} T(n,k).

Links

Eric W. Weisstein, Table of n, a(n) for n = 4..92

Eric Weisstein's World of Mathematics, Chordless Cycle Polynomial.

Eric Weisstein's World of Mathematics, Polygon Diagonal Intersection Graph.

Example

Terms as chordless cycle polynomials:
n=3: 0
n=4: x^4
n=5: 2*x^5 + 15*x^6
n=6: 6*x^4 + 6*x^5 + 25*x^6 + 24*x^7 + 30*x^8 + 24*x^9 + 15*x^10 + 18*x^11 + 18*x^12

Crossrefs

Cf. A362537 (number of chordless cycles in the n-diagonal intersection graph).

Sequence in context: A372974 A104773 A371895 * A363483 A128759 A066582

Adjacent sequences: A371337 A371338 A371339 * A371341 A371342 A371343

Keyword

nonn,more

Author

Eric W. Weisstein, Mar 19 2024

Status

approved