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A063069
Positive integers n such that phi(n) - d(n) = phi(n+1) - d(n+1) where d(n) is the number of divisors of n.
1
45, 104, 345, 3255, 17534, 22935, 70634, 983775, 1025504, 1156701, 2200694, 2619705, 2745765, 4163355, 4447064, 4695704, 6372794, 9718904, 11903775, 23992215, 26879684, 29357475, 37239735, 40588485, 41207144, 42694197, 48615735, 56424555, 76466985
OFFSET
1,1
LINKS
Giovanni Resta, Table of n, a(n) for n = 1..411 (terms < 10^12, a(1)-a(33) from Harry J. Smith, a(34)-a(100) from Donovan Johnson)
PROG
(PARI) for(n=1, 10^5, if(eulerphi(n)-numdiv(n)==eulerphi(n+1)-numdiv(n+1), print(n)))
(PARI) { n=0; s=1; for (m=1, 10^9, if (s!=(r=(eulerphi(m) - numdiv(m))), s=r, write("b063069.txt", n++, " ", m - 1); if (n==100, break)) ) } \\ Harry J. Smith, Aug 16 2009
CROSSREFS
Sequence in context: A350332 A247887 A369185 * A067828 A144552 A068355
KEYWORD
hard,nonn
AUTHOR
Jason Earls, Aug 04 2001
EXTENSIONS
More terms from Naohiro Nomoto, Nov 04 2001
More terms from Harry J. Smith, Aug 16 2009
STATUS
approved