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A143837
a(n) = A066839(A141037(n)).
2
1, 3, 4, 6, 7, 10, 11, 16, 21, 24, 26, 39, 45, 52, 66, 73, 93, 99, 102, 105, 110, 111, 118, 153, 180, 194, 240, 251, 301, 331, 435, 479, 487, 504, 513, 518, 525, 546, 748, 753, 921, 993, 1202, 1285, 1352, 1600, 1716, 1869, 1902, 2221, 2477, 2601, 2640, 2807
OFFSET
1,2
LINKS
FORMULA
a(n) = A066839(A141037(n)).
EXAMPLE
The value of 16 in this sequence corresponds to 1+2+3+4+6 = 16 with 1, 2, 3, 4 and 6 being the divisors of 36 <= sqrt(36).
MAPLE
A066839 := proc(n) a := 0 ; for k in numtheory[divisors](n) do if k^2 <= n then a := a+k ; fi; od: a ; end: A143837 := proc() rec := -1; for n from 1 do r := A066839(n) ; if r > rec then printf("%d, ", r) ; rec := r; fi; od: end: A143837() ; # R. J. Mathar, Nov 03 2008
PROG
(PARI) lista(nn) = {my(ms = 0); for (n=1, nn, sqn = sqrt(n); s = sumdiv(n, d, d*(d<=sqn)); if (s > ms, print1(s, ", "); ms = s); ); } \\ Michel Marcus, Oct 05 2015
CROSSREFS
Sequence in context: A065135 A229792 A101299 * A354005 A330172 A206903
KEYWORD
nonn
AUTHOR
J. Lowell, Sep 02 2008
EXTENSIONS
More terms from R. J. Mathar, Nov 03 2008
Name edited by Jon E. Schoenfield at the suggestion of Joerg Arndt, Oct 12 2015
STATUS
approved