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A121519 Number of primitive roots of prime A103203(n). 2
1, 2, 4, 8, 10, 12, 16, 22, 24, 28, 40, 52, 64, 72, 82, 84, 88, 112, 128, 130, 132, 144, 156, 172, 178, 190, 192, 232, 238, 250, 252, 276, 280, 292, 324, 358, 384, 396, 400, 418, 424, 430, 442, 448, 480, 490, 508, 520, 544, 552, 592, 612, 640, 652, 658, 682, 712 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Also records in A008330.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

EXAMPLE

Prime A103203(5) = 23 has 10 primitive roots, so a(5) = 10; 23 = prime(9) and A008330(9) = 10 is a record in A008330.

PROG

(PARI) r=0; for(n=1, 230, k=eulerphi(prime(n)-1); if(r<k, r=k; print1(k, ", ")))

CROSSREFS

Cf. A008330, A103203.

Sequence in context: A166936 A166245 A276623 * A098968 A032368 A134533

Adjacent sequences:  A121516 A121517 A121518 * A121520 A121521 A121522

KEYWORD

nonn,changed

AUTHOR

Klaus Brockhaus, Aug 06 2006

STATUS

approved

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Last modified September 25 12:38 EDT 2021. Contains 347654 sequences. (Running on oeis4.)