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A209195 Smallest prime factor of the n-th highly totient number (A097942(n)) plus 1. 1
2, 3, 5, 3, 13, 5, 7, 73, 5, 241, 433, 13, 577, 7, 1153, 11, 43, 29, 7, 8641, 41, 11, 7, 30241, 17, 61, 47, 31, 13, 11, 103681, 73, 161281, 13, 7, 241921, 19, 41, 293, 11, 17, 1451521, 31, 2177281, 83, 2903041, 11, 4354561, 109, 5806081, 13, 8709121, 9676801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..109 (calculated from the b-file at A097942)

FORMULA

a(n) = A020639(A097942(n) + 1). - Amiram Eldar, Jul 08 2019

CROSSREFS

Cf. A020639, A097942.

Sequence in context: A323704 A272202 A244609 * A113222 A060444 A002587

Adjacent sequences:  A209192 A209193 A209194 * A209196 A209197 A209198

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Mar 05 2012

EXTENSIONS

More terms from Amiram Eldar, Jul 08 2019

STATUS

approved

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Last modified September 26 05:00 EDT 2020. Contains 337346 sequences. (Running on oeis4.)