OFFSET
1,4
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..64
V. A. Liskovets, Some easily derivable sequences, J. Integer Sequences, 3 (2000), #00.2.2.
FORMULA
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, May 24 2000
EXTENSIONS
Terms a(19) and beyond from Andrew Howroyd, Jan 16 2022
STATUS
approved