A236027 Decimal expansion of 5^(1/2) - 7^(1/3).

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

Offset

0,1

Comments

Decimal expansion of minimal value of the function delta(n) = (n+1)^(1/2) - sigma(n)^(1/tau(n)) for n = 4, where delta(n) is called the delta-deviation from primality of the number n (see A236025).

The positive root of x^6 - 15*x^4 + 14*x^3 + 75*x^2 + 210*x - 76. - Charles R Greathouse IV, Apr 05 2026

Links

Table of n, a(n) for n=0..99.

Index entries for algebraic numbers, degree 6

Formula

Equals A002163 - A005482.

Example

0.32313679472740059521005682...

Mathematica

RealDigits[Sqrt[5] - Surd[7, 3], 10, 120][[1]] (* Amiram Eldar, Jun 06 2023 *)

Prog

(PARI) polrootsreal(x^6 - 15*x^4 + 14*x^3 + 75*x^2 + 210*x - 76)[2] \\ Charles R Greathouse IV, Apr 05 2026

Crossrefs

Cf. A236020, A236021, A236022, A236023, A236024, A236025, A236026.

Cf. A002163, A005482.

Sequence in context: A177462 A106584 A213940 * A220128 A371172 A324468

Adjacent sequences: A236024 A236025 A236026 * A236028 A236029 A236030

Keyword

cons,nonn

Author

Jaroslav Krizek, Jan 19 2014

Status

approved