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A316347
a(n) = n^2 mod(10^m), where m is the number of digits in n (written in base 10).
3
0, 1, 4, 9, 6, 5, 6, 9, 4, 1, 0, 21, 44, 69, 96, 25, 56, 89, 24, 61, 0, 41, 84, 29, 76, 25, 76, 29, 84, 41, 0, 61, 24, 89, 56, 25, 96, 69, 44, 21, 0, 81, 64, 49, 36, 25, 16, 9, 4, 1, 0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 0, 21, 44, 69, 96, 25, 56, 89, 24, 61, 0, 41, 84, 29
OFFSET
0,3
COMMENTS
The set of the terms is the same as that of A238712.
LINKS
Georg Fischer, Table of n, a(n) for n = 0..10000, Jan 16 2019 (terms a(0..719585) initially submitted by Christopher D Chamness).
EXAMPLE
n = 13 has 2 digits in base 10, thus a(13) = 169 mod 100 = 69.
PROG
(Python)
i=1
while True:
m=i
j=i**2
l=0
while True:
m=m/10
l+=1
if m==0:
break
mod_num = 10**l
print j%mod_num
i+=1
(PARI) a(n) = n^2 % 10 ^ #digits(n) \\ David A. Corneth, Jun 30 2018
(Perl) my $mod = 10;
foreach my $i(0..10000) {
print "$i " . (($i * $i) % $mod) . "\n";
if (length($i + 1) > length($i)) { $mod *= 10; }
} # Georg Fischer, Jan 16 2019
CROSSREFS
Cf. A238712.
Sequence in context: A200632 A186723 A008959 * A169917 A059729 A184988
KEYWORD
nonn,base,easy
AUTHOR
STATUS
approved