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A318964
Numbers k such that both k and k+1 are the product of exactly five distinct primes.
5
378014, 421134, 483405, 486590, 486794, 489345, 507129, 545258, 549185, 558789, 558830, 634809, 637329, 663585, 667029, 690234, 720290, 776985, 782690, 823745, 824109, 853005, 853034, 855645, 873885, 883245, 892905, 935714, 945230, 968253, 987734, 999005, 1005081, 1013726
OFFSET
1,1
LINKS
EXAMPLE
n | a(n) | a(n)+1
--+--------------------------------+--------------------------------
1 | 378014 = 2 * 7 * 13 * 31 * 67 | 378015 = 3 * 5 * 11 * 29 * 79
2 | 421134 = 2 * 3 * 7 * 37 * 271 | 421135 = 5 * 11 * 13 * 19 * 31
3 | 483405 = 3 * 5 * 13 * 37 * 67 | 483406 = 2 * 7 * 11 * 43 * 73
PROG
(PARI) is(n) = omega(n)==5 && omega(n+1)==5 && bigomega(n)==5 && bigomega(n+1)==5 \\ Felix Fröhlich, Sep 06 2018
CROSSREFS
Subsequence of A140079.
Sequence in context: A089444 A203740 A283030 * A226361 A238078 A133975
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 06 2018
STATUS
approved