A344554 - OEIS

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A344554

Decimal expansion of 2*(1+sqrt(26))/5.

2, 4, 3, 9, 6, 0, 7, 8, 0, 5, 4, 3, 7, 1, 1, 3, 9, 3, 2, 0, 1, 1, 2, 8, 9, 6, 4, 3, 6, 0, 9, 1, 1, 2, 7, 9, 5, 8, 2, 5, 5, 0, 8, 3, 7, 8, 4, 3, 9, 8, 3, 8, 5, 6, 3, 0, 3, 3, 9, 8, 8, 3, 2, 1, 7, 7, 0, 3, 7, 3, 4, 5, 2, 8, 2, 4, 8, 8, 9, 6, 7, 8, 2, 3, 5, 3, 3, 9, 5, 4, 0, 4, 3, 7

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OFFSET

1,1

COMMENTS

Dissect the unit square into 5 regions with equal areas from a given midpoint on the squares edge. This sequence gives the decimal expansion of the perimeter of the triangular region with unit height.

LINKS

Table of n, a(n) for n=1..94.

FORMULA

Decimal expansion of 2*(1 + k*sqrt(1/k^2 + 1))/k, where k = 5.

EXAMPLE

2.43960780543711393201128964360...

MATHEMATICA

RealDigits[2 (1 + Sqrt[26])/5, 10, 200][[1]] // Flatten

CROSSREFS

Similar sequences into k regions: A344520 (k=3), A343069 (k=7), A344568 (k=9), A344569 (k=17).

Sequence in context: A350150 A111390 A349323 * A129596 A356222 A329901

Adjacent sequences: A344551 A344552 A344553 * A344555 A344556 A344557

KEYWORD

nonn,cons

AUTHOR

Wesley Ivan Hurt, May 23 2021

STATUS

approved