A061505 Leading digit of n^n.

1, 1, 4, 2, 2, 3, 4, 8, 1, 3, 1, 2, 8, 3, 1, 4, 1, 8, 3, 1, 1, 5, 3, 2, 1, 8, 6, 4, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 3, 3, 5, 6, 8, 1, 1, 2, 3, 5, 7, 1, 1, 3, 4, 8, 1, 2, 3, 6, 1, 2, 4, 7, 1, 2, 5, 1, 2, 4, 8, 1, 3, 8, 1, 3, 8, 1, 4, 1, 2, 5, 1, 3, 7, 1, 4, 1, 2, 7, 1, 5, 1, 3, 1, 2, 7, 2, 5, 1

Offset: 0

Author

Amarnath Murthy, May 06 2001

Keywords

• base
• nonn
• easy

Comments

The sequence equals 2 in the range n = 3628..3730. - Rémy Sigrist, Dec 13 2018

Examples

			a(7) = 8, as 7^7 = 823543.
		

Links

• Rémy Sigrist, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A056849.

Programs

Mathematica

a = {}; Do[ a = Append[ a, IntegerDigits[ n^n ] [ [ 1 ] ] ], {n, 1, 75 } ]; a

PARI

a(n) = digits(n^n)[1] \\ Rémy Sigrist, Dec 13 2018

Formula

Using the formula in A000030: a(n) = [n^n / 10^([log_10(n^n)])] = [n^n / 10^([n*log_10(n)])].

Extensions

More terms from Robert G. Wilson v, May 10 2001

Further terms from Asher Auel, May 20 2001

a(0) = 1 prepended by Rémy Sigrist, Dec 13 2018