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A072460 Smallest even nontotient number of which the largest prime divisor equals n-th prime. 0
50, 14, 154, 26, 34, 38, 230, 174, 62, 74, 246, 86, 94, 318, 118, 122, 134, 142, 146, 158, 830, 534, 194, 202, 206, 214, 218, 678, 254, 1310, 274, 278, 298, 302, 314, 326, 334, 1730, 1074, 362, 1146, 386, 394, 398, 422, 446, 454, 458, 2330, 1434, 482, 1506 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

LINKS

Table of n, a(n) for n=3..54.

FORMULA

a(n)=Min{x; A006530[A005277(x)=p[n]=A000040(n), n>2}

EXAMPLE

First even nontotient of which largest prime-factor is p(31)=127, equals 254=A005277[41], the 41st, a(31)=254; 2 and 3 are never largest prime factors of even nontotient numbers.

CROSSREFS

Cf. A006530, A005277.

Sequence in context: A187697 A048178 A317619 * A248128 A033370 A090691

Adjacent sequences:  A072457 A072458 A072459 * A072461 A072462 A072463

KEYWORD

nonn

AUTHOR

Labos Elemer, Jun 19 2002

STATUS

approved

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Last modified April 20 08:48 EDT 2019. Contains 322306 sequences. (Running on oeis4.)