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A095748 Almost maximally asymmetric primes in binary. 4
17, 31, 37, 41, 47, 59, 61, 67, 89, 97, 103, 139, 149, 163, 197, 263, 269, 283, 293, 307, 353, 359, 379, 389, 409, 433, 439, 449, 461, 499, 541, 557, 607, 613, 631, 659, 727, 743, 809, 829, 877, 929, 941, 953, 997, 1009, 1039, 1051, 1151, 1171 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes p for which A037888(p) = floor((A070939(p)-4)/2). Those numbers contain just two bits mirroring each other, beyond the first and last bits. (All the odd primes without leading zeros begin and end in 1 bits.)

LINKS

Table of n, a(n) for n=1..50.

A. Karttunen, J. Moyer: C-program for computing the initial terms of this sequence

EXAMPLE

a(5)=(101111)2. In this case, from left to right, the third bit agrees with the fourth. The prime 53 = (110101)_2 is not a term since the symmetry is limited to the first and last bits.

PROG

(PARI) A070939(p) = { return(floor(log(p)/log(2))+1) };

A037888(p)={v=binary(p); s=0; j=#v; for(k=1, #v, s+=abs(v[k]- v[j]); j--); return(s/2); }; forprime(p=3, 1171, if(A037888(p)==floor((A070939(p)-4)/2), print1(p, ", ")))

CROSSREFS

Cf. A095758, A095749, A095743.

Sequence in context: A002675 A333855 A321217 * A235920 A268923 A172287

Adjacent sequences:  A095745 A095746 A095747 * A095749 A095750 A095751

KEYWORD

nonn,base

AUTHOR

Antti Karttunen, Jun 12 2004

EXTENSIONS

Edited by Washington Bomfim, Jan 13 2011

STATUS

approved

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Last modified July 15 04:34 EDT 2020. Contains 335763 sequences. (Running on oeis4.)