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A087085 Sum of the integer elements in the subsets of the subsets of the integers 1 to n. 0
0, 0, 2, 48, 3072, 2621440, 515396075520, 6198106008766409342976, 304893000761160863263183648258864317464576 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

REFERENCES

Alan Sutcliffe, Divisors and Common Factors in Sets of Integers, awaiting publication.

LINKS

Table of n, a(n) for n=0..8.

FORMULA

n*(n-1)*2^(n-4+2^(n-1))

EXAMPLE

a(3)=48 since the 16 subsets of the sets ( ) (1) (2) (1,2) are ( ) (( )) ((1)) ((2)) ((1,2)) (( ) (1)) (( ) (2)) (( ) (1,2)) ((1) (2)) ((1) (1,2)) ((2) (1,2)) (( ) (1) (2)) (( ) (1) (1,2)) (( ) (2) (1,2)) ((1) (2) (1,2)) (( ) (1) (2) (1,2)) and the sum of the 32 integer elements is 48.

CROSSREFS

A001146 gives the number of subsets of the subsets of the integers 1 to n. A028369 gives the number of subset elements in the subsets of the subsets of the integers 1 to n. A087084 gives the number of integer elements in the subsets of the subsets of the integers 1 to n.

Sequence in context: A186416 A210723 A322750 * A067626 A053071 A238838

Adjacent sequences:  A087082 A087083 A087084 * A087086 A087087 A087088

KEYWORD

easy,nonn

AUTHOR

Alan Sutcliffe (alansut(AT)ntlworld.com), Aug 13 2003

STATUS

approved

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Last modified August 18 07:11 EDT 2019. Contains 326072 sequences. (Running on oeis4.)