A077651 - OEIS

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A077651

Initial digit of phi(n), where phi is Euler totient function, A000010.

1, 1, 2, 2, 4, 2, 6, 4, 6, 4, 1, 4, 1, 6, 8, 8, 1, 6, 1, 8, 1, 1, 2, 8, 2, 1, 1, 1, 2, 8, 3, 1, 2, 1, 2, 1, 3, 1, 2, 1, 4, 1, 4, 2, 2, 2, 4, 1, 4, 2, 3, 2, 5, 1, 4, 2, 3, 2, 5, 1, 6, 3, 3, 3, 4, 2, 6, 3, 4, 2, 7, 2, 7, 3, 4, 3, 6, 2, 7, 3, 5, 4, 8, 2, 6, 4, 5, 4, 8, 2, 7, 4, 6, 4, 7, 3, 9, 4, 6, 4, 1, 3, 1, 4, 4

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A000030(A000010(n)).

MATHEMATICA

Table[First[IntegerDigits[EulerPhi[w]]], {w, 1, 128}]

PROG

(PARI) A077651(n) = (digits(eulerphi(n))[1]); \\ Antti Karttunen, Dec 04 2017

CROSSREFS