login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A255850
Number of digits in the n-th term of A061844: Squares which remain squares if you decrease every digit by 1.
2
1, 2, 4, 5, 7, 11, 12, 18, 20, 20, 20, 21, 30, 30, 30, 30, 30, 30, 30, 30, 32, 32, 32, 40, 42, 42, 42, 42, 42, 42, 42, 42, 42, 54, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60
OFFSET
1,2
COMMENTS
Suggested by W. Appleby in a Number Theory discussion group, cf. link.
LINKS
G. Campbell et al., A six digit problem, Number Theory group on LinkedIn.com, March 2015.
FORMULA
a(n) = A055642(A061844(n)).
PROG
(PARI) a(n)=#Str(A061844(n)) \\ if A061844 is a function
(PARI) A255850=apply(t->#Str(t), A061844) \\ if A061844 is a vector
CROSSREFS
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Mar 10 2015
EXTENSIONS
More terms calculated from A061844 by Lars Blomberg, Aug 21 2016
STATUS
approved