A061464 Denominator of 1/(1^1) + 1/(2^2) + 1/(3^3) + ... 1/(n^n).

1, 1, 4, 108, 6912, 21600000, 583200000, 480290277600000, 31476303632793600000, 16727798278915463577600000, 52274369621610823680000000000, 14914487726878692033020558868480000000000

Offset

0,3

Links

Table of n, a(n) for n=0..11.

Formula

A061463(n)/a(n) = Integral_{x=0..1} Gamma(n, -x*log(x))/(x^x*Gamma(n)) dx. - Thomas Scheuerle, Feb 26 2025

Example

1, 5/4, 139/108, 8923/6912,...

Maple

summ := 0; for n from 1 to 15 do printf("%d ", denom(summ)); if (1 = 1) then summ := summ + 1/n^n: end if; od;

Mathematica

Join[{1}, Denominator/@Table[Sum[1/i^i, {i, n}], {n, 12}]] (* Harvey P. Dale, Jul 03 2011 *)

Prog

(PARI) a(n) = denominator(sum(k=1, n, 1/(k^k))) \\ Thomas Scheuerle, Feb 26 2025

Crossrefs

Cf. A061463, A073009.

Sequence in context: A123056 A024263 A090205 * A107048 A269187 A185702

Adjacent sequences: A061461 A061462 A061463 * A061465 A061466 A061467

Keyword

nonn,frac,easy,changed

Author

Amarnath Murthy, May 04 2001

Extensions

More terms from Winston C. Yang (winston(AT)cs.wisc.edu), May 19 2001

a(12) from Harvey P. Dale, Jul 03 2011

Status

approved