

A177266


Triangle read by rows: R(n,k)=2^(semiprime(n)semiprime(k)) mod semiprime(n).


0



1, 4, 1, 5, 8, 1, 4, 6, 2, 1, 2, 4, 4, 2, 1, 8, 2, 4, 2, 2, 1, 11, 8, 1, 11, 2, 1, 1, 14, 20, 8, 4, 14, 18, 2, 1, 2, 13, 11, 18, 23, 24, 16, 8, 1, 10, 22, 6, 16, 14, 20, 6, 16, 2, 1, 17, 29, 16, 8, 17, 25, 4, 2, 25, 29, 1, 30, 16, 2, 18, 16, 8, 32, 16, 2, 18, 2, 1, 23, 32, 4, 2, 22
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OFFSET

1,2


LINKS

Table of n, a(n) for n=1..83.


EXAMPLE

Triangle begins:
1,
4, 1,
5, 8, 1,
4, 6, 2, 1,
2, 4, 4, 2, 1,
8, 2, 4, 2, 2, 1,


PROG

(PARI) trg(nn) = {semip = select(n>bigomega(n) == 2, vector(nn, i, i)); for (n = 1, #semip, for (k = 1, n, print1(2^(semip[n]  semip[k]) % semip[n], ", "); ); print(); ); } \\ Michel Marcus, Sep 11 2013


CROSSREFS

Cf. A000079, A001358, A173622, A174479, A176066, A181615.
Sequence in context: A058662 A133866 A242131 * A272534 A332522 A173386
Adjacent sequences: A177263 A177264 A177265 * A177267 A177268 A177269


KEYWORD

nonn,tabl


AUTHOR

JuriStepan Gerasimov, Dec 10 2010


EXTENSIONS

Corrected by D. S. McNeil, Dec 10 2010


STATUS

approved



