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A173586
Decimal values a(n) of the binary numbers b(n) obtained by starting from first prime number (2), sequentially concatenating the binary representation of all prime numbers till n-th prime, and after that, sequentially concatenating the binary representation of all prime numbers, from (n-1)th till the first prime.
0
2, 46, 1502, 96222, 12316638, 3153031134, 1614350348254, 1653094690025438, 1692768964130074590, 1733395419356639752158, 1774996909423485572837342, 3635193670499109531489365982
OFFSET
1,1
FORMULA
a(n) = binary_to_decimal(concatenate(10, 11, 101, ..., binary((n-2)th prime), binary((n-1)th prime), binary(n-th prime), binary((n-1)th prime), binary((n-2)th prime), ..., 101, 11, 10))
EXAMPLE
a(1)=binary_to_decimal(10)=2, a(2)=binary_to_decimal(101110)=46, a(3)=binary_to_decimal(10111011110)=1502, a(4)=binary_to_decimal(10111011111011110)=96222 etc.
CROSSREFS
Cf. A066622. This sequence uses the term generation rule of A066622 (Concatenation of prime numbers in increasing order up to the n-th and then in decreasing order.), albeit with the binary base instead of the decimal base.
Sequence in context: A012006 A279524 A264500 * A074041 A277554 A000191
KEYWORD
base,nonn
AUTHOR
Umut Uludag, Feb 22 2010
STATUS
approved