OFFSET
1,17
LINKS
Iain Fox, Table of n, a(n) for n = 1..10000
PROG
(PARI) a(n) = my(c); for(i=2, #n=digits(n, 4), if(abs(n[i]-n[i-1])==1, c++)); c \\ Iain Fox, Oct 27 2018
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved