id:A039777 - OEIS Search Results

Search: id:A039777

Displaying 1-1 of 1 results found.

page 1

phi(a(n)) is equal to the sum of (the product of prime factors and the products of exponents) of (a(n)-1).

+0
1

2, 5, 21, 45, 285, 765, 27645, 196605, 41067645, 72787965 (list; graph; listen)

	OFFSET	`1,1`
	COMMENT	`Next term if it exists is >= 10^8.`
	EXAMPLE	`phi(21)=12, 20=2^25^1, (22)+(5*1)=20.`
	CROSSREFS	`Cf. A000010, A039696.` `Sequence in context: A006893 A003163 A088498 this_sequence A000941 A000131 A152801` `Adjacent sequences: A039774 A039775 A039776 this_sequence A039778 A039779 A039780`
	KEYWORD	`nonn,hard`
	AUTHOR	`Olivier Gerard (olivier.gerard(AT)gmail.com)`
	EXTENSIONS	`More terms from Jud McCranie (j.mccranie(AT)comcast.net)`

page 1

Search completed in 0.002 seconds

Last modified November 25 13:42 EST 2009. Contains 167481 sequences.