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 A086904 Write the primes in binary; a(n) = total number of 0's in those which have an n-bit expansion. 1
 1, 1, 2, 7, 13, 35, 71, 147, 298, 622, 1270, 2558, 5257, 10509, 21297, 42852, 86258, 173528, 348187, 699590, 1404936, 2818606, 5657411, 11345622, 22746823 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,3 LINKS EXAMPLE a(2) = 1: 2 = 10 and 3 = 11, with a total of one 0. a(3) = 1: 5 = 101, 7 = 111, again with just one 0. PROG (PARI) a(n) = {nb = 0; for (i=2^(n-1), 2^n-1, if (isprime(i), nb += n - norml2(binary(i))); ); return (nb); } \\ Michel Marcus, Jun 20 2013 CROSSREFS Cf. A168156. Sequence in context: A079119 A309368 A051748 * A291276 A217305 A026555 Adjacent sequences:  A086901 A086902 A086903 * A086905 A086906 A086907 KEYWORD base,nonn AUTHOR Jacob Woolcutt (woolcutt(AT)uiuc.edu), Sep 19 2003 STATUS approved

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Last modified October 13 16:10 EDT 2019. Contains 327966 sequences. (Running on oeis4.)