cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A227589 Maximum label within a minimal labeling of n identical 4-sided dice yielding the most possible sums.

Original entry on oeis.org

1, 4, 7, 12, 16, 23, 29, 38, 46, 57, 67, 80, 92, 107, 121, 138, 154, 173, 191, 212, 232
Offset: 0

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Author

Jens Voß, Jul 17 2013

Keywords

Examples

			Three tetrahedra labeled (1, 2, 8, 12) yield the 20 possible sums 3, 4, 5, 6, 10, 11, 12, 14, 15, 16, 17, 18, 21, 22, 24, 25, 26, 28, 32, 36. No more sums can be obtained by different labelings, and no labeling with labels < 12 yields 20 possible sums. Therefore a(3) = 12.
		

Crossrefs

Row n=4 of array A227588.

Formula

Conjecture: a(n) = (n^2 + 3n + 5 - (-1)^n)/2 for n > 1.
Conjecture: a(n) = 2*a(n-1)-2*a(n-3)+a(n-4) for n>5. G.f.: (x^5-x^4-x^2+2*x+1) / ((x-1)^3*(x+1)). - Colin Barker, Aug 01 2013