A316347 a(n) = n^2 mod(10^m), where m is the number of digits in n (written in base 10).

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

Adjacent sequences: A316344 A316345 A316346 * A316348 A316349 A316350

Keyword

nonn,base,easy

Author

Christopher D Chamness, Jun 29 2018

Status

approved