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A307507 Brazilian semiprimes. 1
10, 14, 15, 21, 22, 26, 33, 34, 35, 38, 39, 46, 51, 55, 57, 58, 62, 65, 69, 74, 77, 82, 85, 86, 87, 91, 93, 94, 95, 106, 111, 115, 118, 119, 121, 122, 123, 129, 133, 134, 141, 142, 143, 145, 146, 155, 158, 159, 161, 166, 177, 178, 183, 185, 187, 194, 201, 202, 203, 205, 206, 209, 213, 214, 215, 217, 218 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Comparison with A001358 (semiprimes): in this sequence, there are no squared primes apart from 121 = (11111)_3, and also 6 is missing from here since it is not Brazilian.

Different from the squarefree semiprimes of A006881: this sequence = {A006881 \ 6} Union {121}.

LINKS

Table of n, a(n) for n=1..67.

EXAMPLE

a(20) = 74 = 2 * 37 = (22)_36 is semiprime and Brazilian.

25 = 5 * 5 is semiprime and no Brazilian, and 45 = (55)_8 = (33)_14 = 3^2 * 5 is Brazilian but no semiprime.

CROSSREFS

Intersection of A001358 and A125134.

Cf. A006881, A131317, A190300.

Sequence in context: A100929 A307980 A087247 * A171156 A235690 A271568

Adjacent sequences:  A307504 A307505 A307506 * A307508 A307509 A307510

KEYWORD

nonn,base

AUTHOR

Bernard Schott, Apr 11 2019

STATUS

approved

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Last modified February 27 15:59 EST 2020. Contains 332307 sequences. (Running on oeis4.)