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A333100 Even numbers k such that both k and k + 2 are nontotients (A005277). 3
74, 122, 152, 186, 234, 242, 244, 246, 284, 302, 338, 362, 374, 402, 404, 410, 412, 426, 434, 470, 472, 482, 494, 514, 516, 530, 532, 548, 572, 594, 602, 608, 626, 666, 668, 678, 722, 728, 746, 752, 788, 802, 804, 842, 844, 866, 868, 870, 872, 890, 892, 914, 942 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

Eric Weisstein's World of Mathematics, Nontotient.

Wikipedia, Nontotient.

EXAMPLE

74 is a term since both 74 and 76 are nontotients.

PROG

(PARI) forstep(k=2, 100, 2, if(!istotient(k) && !istotient(k+2), print1(k, ", ")))

CROSSREFS

Cf. A005277, A063512, A231964, A306952, A333101.

Sequence in context: A066132 A045283 A118221 * A270340 A300379 A300681

Adjacent sequences:  A333097 A333098 A333099 * A333101 A333102 A333103

KEYWORD

nonn

AUTHOR

Amiram Eldar, Mar 07 2020

STATUS

approved

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Last modified January 16 15:21 EST 2021. Contains 340206 sequences. (Running on oeis4.)