OFFSET
1,2
LINKS
PROG
(Scheme, requiring also defineperm1-macro from Antti Karttunen's IntSeq-library)
;; When A218252 is defined with defineperm1-macro, it will automatically cache also the inverse values, which are then available with negative arguments:
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 04 2015
STATUS
approved