A269243 Number of times the digit 3 appears in the decimal expansion of n^3.

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

Offset: 0

Author

M. F. Hasler, Feb 20 2016

Keywords

• nonn
• base

Comments

The cubes corresponding to the first occurrence of 1, 2, 3, ... are listed in A036530, i.e., A036530(n)^(1/3) = A048368(n) is the index of the first occurrence of n.

Examples

			0^3 = 0, 1^3 = 1, 2^3 = 8, 3^3 = 27, 4^3 = 64, 5^3 = 125 and 6^3 = 216 all have a(0) = a(1) = ... = a(6) = 0 digits '3'.
7^3 = 343 has a(7) = 2 digits '3'.
		

Crossrefs

Cf. A036530 and A036527 - A036536; A048368 and A048365 - A048374.

Analog for the other digits 0, 1, ..., 9: A269250, A269241, A269242, A269243, A269244, A269245, A269246, A269247, A269248, A269249.

Analog for squares: A086011 (digit 3), and A086008 - A086017 for digits 0 - 9.

Programs

Mathematica

Table[DigitCount[n^3, 10, 3], {n, 0, 100}] (* Robert Price, Mar 21 2020 *)

PARI

A269243(n)=#select(t->t==3,digits(n^3))