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A096504
Euler-phi applied to A096503 results in these decimal repdigits.
4
1, 1, 2, 2, 4, 2, 6, 4, 6, 4, 4, 6, 8, 8, 6, 8, 22, 8, 8, 22, 66, 44, 88, 44, 88, 66, 44, 88, 88, 222, 88, 88, 222, 444, 444, 888, 888, 444, 888, 888, 888, 888, 888, 888, 444444, 666666, 444444, 888888, 888888, 666666, 888888, 888888, 888888, 888888, 888888
OFFSET
1,3
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..182 (calculated using the b-file at A096503)
FORMULA
a(n) = A000010(A096503(n)).
EXAMPLE
a(60) = A000010(A096503(60)) = A000010(88888892) = 44444444.
Regular solutions: if p = repdigit + 1 is prime, then phi(p) = repdigit.
PROG
(PARI) lista(nn) = {for (n= 1, nn, phin = eulerphi(n); d = digits(e=eulerphi(n)); if (vecmin(d) == vecmax(d), print1(e, ", ")); ); } \\ Michel Marcus, Sep 07 2014
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Labos Elemer, Jul 12 2004
STATUS
approved