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A134806 Partition numbers of perfect numbers. 1
11, 3718, 1842351033503159891466 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(4) ~ 4.799...*10^95, a(5) ~ 1.849...*10^6444, a(6) ~ 1.852...*10^103237. - Amiram Eldar, Mar 16 2019

a(4) has 96 digits and a(5) has 6445 digits. - Harvey P. Dale, Jan 17 2022

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..4

FORMULA

a(n) = A000041(A000396(n)).

EXAMPLE

a(2)=3718 because the second perfect number is A000396(2)=28 and the partition number of 28 is A000041(28)=3718.

MATHEMATICA

mers[n_] := 2^(n-1)*(2^n-1); a[n_] := PartitionsP[mers[MersennePrimeExponent[n]]]; a/@Range[4] (* Amiram Eldar, Mar 15 2019, assuming that all the perfect numbers are even *)

PartitionsP[PerfectNumber[Range[5]]] (* Harvey P. Dale, Jan 17 2022 *)

CROSSREFS

Cf. A000041, A000396.

Sequence in context: A214137 A295192 A295195 * A024152 A265958 A147668

Adjacent sequences:  A134803 A134804 A134805 * A134807 A134808 A134809

KEYWORD

bref,nonn

AUTHOR

Omar E. Pol, Nov 13 2007

STATUS

approved

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Last modified May 20 01:04 EDT 2022. Contains 353847 sequences. (Running on oeis4.)