login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A242139 Decimal equivalents of A242138. 4
5, 9, 10, 17, 18, 21, 27, 33, 34, 36, 42, 45, 51, 54, 65, 66, 68, 73, 85, 99, 102, 119, 129, 130, 132, 136, 146, 153, 165, 170, 187, 195, 198, 204, 219, 221, 231, 238, 257, 258, 260, 264, 273, 292, 297, 325, 330, 341, 363, 365, 387, 390, 396, 429, 438, 455 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..56.

PROG

(PARI) isvper(v) = {nv = #v; if (isprime(nv), return (0)); fordiv(nv, d, if ((d > 1) && (d < nv), dv = vector(d, i, v[i]); pdv = []; for (k=1, nv/d, pdv = concat(pdv, dv)); if (pdv == v, return (1)); ); ); return (0); }

isok(n) = {vn = binary(n); if (vecmin(vn) == vecmax(vn), return (0)); if (isvper(vn), return (1)); nbmax = #vn; for (k=1, nbmax, vn = concat(0, vn); if (isvper(vn), return (1)); ); return (0); } \\ Michel Marcus, Aug 25 2014

CROSSREFS

Sequence in context: A164709 A212314 A136318 * A216765 A117771 A227853

Adjacent sequences:  A242136 A242137 A242138 * A242140 A242141 A242142

KEYWORD

nonn,base

AUTHOR

Felix Fröhlich, May 05 2014

EXTENSIONS

Missing terms 99, 102, 119 added and more terms from Michel Marcus, Aug 25 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 6 10:34 EDT 2021. Contains 343581 sequences. (Running on oeis4.)