A137116 Numbers k such that k and k^2 use only the digits 2, 5, 7, 8 and 9.

5, 27, 77, 85, 527, 727, 7227, 9777, 28277, 29585, 88277, 99277, 278527, 298827, 2788527, 2789227, 5289227, 8875727, 9889277, 22925527, 27797977, 29879585, 52898827, 85298827, 88875527, 99789227, 99988777, 278889277, 287279585, 292898827, 297875527, 299929585, 527252527, 528982977, 727528527, 727825527, 727925527, 988579585, 992587527

Offset

1,1

Comments

Generated with DrScheme.

Links

Michael S. Branicky, Table of n, a(n) for n = 1..578 (through 20 digits; first 180 terms from Jonathan Wellons)

Jonathan Wellons, Tables of Shared Digits [archived].

Example

727872928279585^2 = 529798999722297889227927772225.

Prog

(Python) # uses auptod in A137110
print(auptod(16, only="25789")) # Michael S. Branicky, May 27 2021

Crossrefs

Cf. A137110, A137117.

Sequence in context: A181890 A048712 A121876 * A137117 A064675 A135713

Adjacent sequences: A137113 A137114 A137115 * A137117 A137118 A137119

Keyword

base,nonn

Author

Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008

Status

approved