A162531 Numbers k whose largest divisor <= sqrt(k) is 11.

121, 132, 143, 154, 165, 176, 187, 198, 209, 220, 231, 242, 253, 275, 297, 319, 341, 363, 385, 407, 451, 473, 517, 539, 583, 605, 649, 671, 737, 781, 803, 847, 869, 913, 979, 1067, 1111, 1133, 1177, 1199, 1243, 1331, 1397, 1441, 1507, 1529, 1639, 1661

Offset

1,1

Comments

See A161344 for more information.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Formula

Numbers k such that A033676(k)=11.

a(n) = 10*prime(n-12) for all n > 42. - M. F. Hasler, Mar 28 2026

Maple

A033676 := proc(n) local dvs; dvs := sort(convert(numtheory[divisors](n), list)) ; op(floor((nops(dvs)+1)/2) , dvs) ; end: for n from 1 to 2500 do if A033676(n) = 11 then printf("%d, ", n) ; fi; od: # R. J. Mathar, Jul 13 2009

Mathematica

ld = 11;
selQ[n_] := AllTrue[Divisors[n], # <= ld || #^2 > n&];
Select[ Range[ld, 200] ld, selQ] (* Jean-François Alcover, Apr 14 2020 *)
ld11Q[n_]:=Max[Select[Divisors[n], #<=Sqrt[n]&]]==11; Select[Range[2000], ld11Q] (* Harvey P. Dale, Nov 27 2025 *)

Prog

(PARI) apply( {A162531(n)=if(n>42, prime(n-12), n<14, n+10, n<21, n*2-3, n*3-if(n<29, 23-n%2, n<36, 19+n%2-n\35*4, 11-n%2-n\42*6))*11}, [1..44]) \\ M. F. Hasler, Mar 28 2026

Crossrefs

Cf. A033676, A008578, A161344, A161345, A161424, A161835, A162526, A162527, A162528, A162529, A162530, A162532.

Sequence in context: A134941 A173070 A044867 * A050697 A319923 A020253

Adjacent sequences: A162528 A162529 A162530 * A162532 A162533 A162534

Keyword

easy,nonn

Author

Omar E. Pol, Jul 05 2009

Extensions

More terms from R. J. Mathar and Jasper Mulder (jasper.mulder(AT)planet.nl), Jul 13 2009

Status

approved