A086010 Number of 2's in decimal expansion of n^2.

0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 2, 1, 0, 0, 1, 0, 0, 0, 0, 0, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 2, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0

Offset

0,16

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Mathematica

DigitCount[(Range[0, 100])^2, 10, 2] (* G. C. Greubel, Dec 13 2016 *)

Prog

(PARI) A086010(n)=#select(d->d==2, digits(n^2)) \\ M. F. Hasler, Feb 21 2016

Crossrefs

Cf. 0's A086008, 1's A086009, 3's A086011, 4's A086012, 5's A086013, 6's A086014, 7's A086015, 8's A086016, 9's A086017.

Cf. A269242 for the n^3 analog.

Sequence in context: A309048 A086072 A086009 * A321929 A089198 A059607

Adjacent sequences: A086007 A086008 A086009 * A086011 A086012 A086013

Keyword

base,nonn

Author

Jason Earls, Jul 07 2003

Status

approved