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A061535
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a(n) = a(n-1) + the number of primes <= a(n-1).
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3
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2, 3, 5, 8, 12, 17, 24, 33, 44, 58, 74, 95, 119, 149, 184, 226, 274, 332, 399, 477, 568, 671, 792, 930, 1088, 1269, 1474, 1707, 1973, 2271, 2608, 2986, 3415, 3895, 4434, 5036, 5710, 6461, 7299, 8229, 9260, 10407, 11681, 13083, 14639, 16354, 18250
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OFFSET
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1,1
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COMMENTS
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Obviously, the first difference is PrimePi(a(n)).
Number of terms less than and equal to 2^k: 1, 2, 4, 5, 7, 10, 13, 16, 20, 24, 29, 34, 39, 46, 52, 59, 67, 75, 83, 92, 101, 111, 122, 132, 144, 156, 168, 181, 194, 208, 222, 237, 252, 268, 284, 301, 318, 335, 353, 372, 391, 411, 431, 451, 472, 494, 516, 538, ....
Number of terms less than 10^k: 4, 12, 24, 41, 64, 91, 124, 163, 206, 255, 310, 369, 434, 505, .... (End)
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LINKS
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MAPLE
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option remember;
if n= 1 then
2;
else
procname(n-1)+numtheory[pi](procname(n-1)) ;
end if;
end proc:
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MATHEMATICA
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a[1] = 2; a[n_] := a[n] = a[n - 1] + PrimePi[ a[n - 1] ]; Table[ a[n], {n, 1, 75} ]
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PROG
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(PARI) { default(primelimit, 4294965247); for (n=1, 238, if (n==1, a=2, a+=primepi(a)); write("b061535.txt", n, " ", a) ) } \\ Harry J. Smith, Jul 24 2009
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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