A097371 Numbers n such that n=(d_1+5)(d_2+5)*...*(d_k+5), where d_1 d_2 ... d_k is the decimal expansion of n.

50, 210, 450, 780, 1500, 3920, 16500, 91728, 269500, 493920, 1293600, 266378112, 317447424, 1277337600, 14948388000, 48697248600, 379748636467200

Offset

1,1

Comments

All terms are even.

No other terms below 10^100. - Max Alekseyev, Jan 26 2015

Links

Table of n, a(n) for n=1..17.

Example

317447424 is in the sequence because 317447424=(3+5)(1+5)(7+5)(4+5)(4+5)(7+5)(4+5)(2+5)(4+5).

Mathematica

Do[h=IntegerDigits[n]; l=Length[h]; If[n==Product[h[[k]]+5, {k, l}], Print[n]], {n, 800000000}]

Crossrefs

Cf. A097372, A098681.

Sequence in context: A115592 A334808 A273293 * A179755 A186843 A250527

Adjacent sequences: A097368 A097369 A097370 * A097372 A097373 A097374

Keyword

base,nonn

Author

Farideh Firoozbakht, Sep 20 2004

Extensions

4 more terms from Giovanni Resta, Jan 13 2006

Status

approved