OFFSET
1,1
COMMENTS
From Robert G. Wilson v, Jan 14 2012: (Start)
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)
LINKS
Robert G. Wilson v, Table of n, a(n) for n = 1..535 (first 300 terms from T. D. Noe)
MAPLE
A061535 := proc(n)
option remember;
if n= 1 then
2;
else
procname(n-1)+numtheory[pi](procname(n-1)) ;
end if;
end proc:
seq(A061535(n), n=1..30); # R. J. Mathar, Jun 18 2021
MATHEMATICA
a[1] = 2; a[n_] := a[n] = a[n - 1] + PrimePi[ a[n - 1] ]; Table[ a[n], {n, 1, 75} ]
NestList[#+PrimePi[#]&, 2, 50] (* Harvey P. Dale, Apr 15 2019 *)
PROG
(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
CROSSREFS
KEYWORD
nonn
AUTHOR
R. K. Guy, Robert G. Wilson v, May 14 2001
STATUS
approved