cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A184864 Numbers m such that prime(m) is of the form floor(n+nr-r/2), where r=(1+sqrt(5))/2; complement of A184861.

Original entry on oeis.org

4, 7, 13, 14, 17, 19, 26, 27, 29, 31, 33, 36, 41, 47, 50, 56, 58, 60, 65, 67, 69, 74, 77, 78, 83, 84, 85, 87, 88, 91, 94, 95, 97, 100, 104, 106, 108, 110, 113, 114, 117, 119, 121, 123, 128, 129, 135, 138, 139, 142, 143, 145, 146, 148, 150, 152, 155, 160, 163, 166, 167, 169, 174, 176, 177, 180, 183, 186, 187, 190, 191, 195, 196, 198, 201, 203, 207, 209, 211, 216, 220, 221, 222, 224, 227, 228, 235, 239, 243, 244, 246, 247
Offset: 1

Views

Author

Clark Kimberling, Jan 23 2011

Keywords

Crossrefs

Programs

  • Mathematica
    r=(1+5^(1/2))/2;
    a[n_]:=Floor [n+n*r-r/2];
    Table[a[n], {n, 1, 120}]  (* A007064 *)
    t1={}; Do[If[PrimeQ[a[n]], AppendTo[t1, a[n]]], {n, 1, 600}]; t1
    t2={}; Do[If[PrimeQ[a[n]], AppendTo[t2, n]], {n, 1, 600}]; t2
    t3={}; Do[If[MemberQ[t1, Prime[n]], AppendTo[t3, n]], {n, 1, 300}]; t3
    *( Lists t1, t2, t3 match A184862, A184863, A184864.)

A184863 Numbers k such that floor(n+nr-r/2) are prime, where r=(1+sqrt(5))/2.

Original entry on oeis.org

3, 7, 16, 17, 23, 26, 39, 40, 42, 49, 53, 58, 69, 81, 88, 101, 104, 108, 120, 127, 133, 143, 149, 152, 165, 166, 168, 172, 175, 179, 188, 191, 195, 207, 218, 221, 227, 230, 236, 237, 246, 250, 253, 259, 275, 278, 291, 301, 305, 314, 315, 317, 321, 328, 330, 337, 347, 360, 370, 376, 379, 386, 395, 401, 402, 409, 418, 424, 427, 440, 441, 454, 456, 464, 470, 473, 489, 493, 496, 505, 525, 528, 535, 544, 548, 550, 567, 573, 590, 592, 596, 599
Offset: 1

Views

Author

Clark Kimberling, Jan 23 2011

Keywords

Crossrefs

Programs

  • Mathematica
    r=(1+5^(1/2))/2;
    a[n_]:=Floor [n+n*r-r/2];
    Table[a[n], {n, 1, 120}]  (* A007064 *)
    t1={}; Do[If[PrimeQ[a[n]], AppendTo[t1, a[n]]], {n, 1, 600}]; t1
    t2={}; Do[If[PrimeQ[a[n]], AppendTo[t2, n]], {n, 1, 600}]; t2
    t3={}; Do[If[MemberQ[t1, Prime[n]], AppendTo[t3, n]], {n, 1, 300}]; t3
    *( Lists t1, t2, t3 match A184862, A184863, A184864.)
    With[{gr=GoldenRatio},Select[Range[600],PrimeQ[Floor[#+gr*#-gr/2]]&]] (* Harvey P. Dale, Jul 06 2025 *)
Showing 1-2 of 2 results.