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A055517 Largest integer k such that k | Phi(k) - d(k) + n, or 0 if no such k exists, where d() is the number of divisors. 0
30, 4, 12, 0, 1, 4, 9, 2, 25, 4, 49, 15, 14, 27, 121, 35, 169, 33, 26, 55, 289, 77, 361, 91, 38, 85, 529, 143, 46, 133, 44, 187, 841, 221, 961, 247, 62, 253, 42, 323, 1369, 217, 74, 391, 1681, 437, 1849, 403, 86, 493, 2209 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

In the case of n = 3, the condition is satisfied for all the primes.

LINKS

Table of n, a(n) for n=0..50.

EXAMPLE

for a(2), 12 | [ Phi(12) + d(12) + 2 ].

CROSSREFS

Cf. A020488.

Sequence in context: A307026 A040882 A040883 * A040884 A040880 A040881

Adjacent sequences:  A055514 A055515 A055516 * A055518 A055519 A055520

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jul 03 2000

STATUS

approved

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Last modified June 23 15:39 EDT 2021. Contains 345402 sequences. (Running on oeis4.)