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.

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

Cf. A000005, A000010.

Sequence in context: A350332 A247887 A369185 * A067828 A144552 A068355

Adjacent sequences: A063066 A063067 A063068 * A063070 A063071 A063072

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