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A195629
Sequence with chaotic first differences: a(1)=2; a(n)=prime((prime(n) mod 10)+pi(a(n-1))).
0
2, 7, 23, 53, 59, 71, 103, 151, 167, 223, 227, 263, 269, 281, 331, 349, 401, 409, 449, 457, 467, 541, 563, 613, 653, 659, 677, 733, 797, 821, 859, 863, 919, 983, 1039, 1049, 1093, 1109, 1171, 1193, 1259, 1277, 1279, 1291, 1327, 1429, 1433, 1451, 1489, 1559, 1579, 1627, 1637, 1657, 1709, 1733, 1801, 1811, 1873, 1877, 1901
OFFSET
1,1
COMMENTS
Sequence with chaotic first differences; minimal values a(n)-a(n-1)=2 occur when prime(n) ==1 mod 10 and a(n-1) is lesser of twin primes (and a(n) the larger of twin primes); corresponding n's are 42, 81, 109, 114, 151, 159, 166, 172, 232, 239, 334, 343, 369, 398, 431, 522, 537, 574, 584, 651, 661, 672, 763, 770, 851, 858, 869, 872, 895, 942.
EXAMPLE
n=2: prime(2)=3, A=(prime(n) mod 10)=3; a(n-1)=2, B=pi(a(n-1))=1; prime(A+B)=prime(3+1)=7 => a(2)=7;
n=3: A=4; B=5; prime(9)=23 => a(3)=23.
CROSSREFS
Sequence in context: A049001 A049002 A247197 * A323526 A011757 A121963
KEYWORD
nonn
AUTHOR
Zak Seidov, Sep 24 2011
EXTENSIONS
Typos in sequence name and comments fixed by Zak Seidov, Nov 01 2011
STATUS
approved