A080130 -id:A080130 - cp's OEIS frontend

A332982 Decimal expansion of Pi/exp(gamma).

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

Offset: 1

Spenser Talkington, Mar 05 2020

Arises in the weak-coupling BCS model of superconductors, from the integral Integral_{0..a} tanh(x)/x dx that approaches log(4*exp(gamma)*a/Pi) as a becomes large.

			1.7638769888620456906926621345433395350860272289667507023134353211210579125900...

J. Bardeen, L. N. Cooper, and J. R. Schrieffer, Theory of Superconductivity, Physical Review, 108 (1957), 1175-1204.

Cf. A000796 (Pi), A001113 (e), A001620 (Euler-Mascheroni constant), A073004 (exp(gamma)), A080130 (exp(-gamma)).

RealDigits[Pi/E^(EulerGamma), 10, 100][[1]]

Pi/exp(Euler) \\ Michel Marcus, Mar 28 2020

A359057 Decimal expansion of 1/(1 - e^(-gamma)).

Original entry on oeis.org

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

Offset: 1

Omar E. Pol, Dec 14 2022

This constant is mentioned by Andreas Weingartner.

			2.2802910165143604282867468123251090181102824133274380534504187669076628...

Andreas Weingartner, The number of prime factors of integers with dense divisors, arXiv preprint arXiv:2101.11585 [math.NT], 2021.

Cf. A001113, A001620, A080130, A174973, A227242.

RealDigits[1/(1 - Exp[-EulerGamma]), 10, 120][[1]] (* Amiram Eldar, Dec 15 2022 *)

1/(1-exp(-Euler)) \\ Michel Marcus, Dec 15 2022

Equals 1/A227242.
Equals 1/(1 - A080130).
Equals 1/(1 - A001113^(-A001620)).

More terms from Alois P. Heinz, Dec 14 2022

cp's OEIS Frontend

A332982 Decimal expansion of Pi/exp(gamma).

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