A115227 Numbers k such that k = (d_1+7)(d_2+7)*...*(d_m+7) where d_1 d_2 ... d_m is the decimal expansion of k.

8314460009856000, 31746120037632000, 92632873013093597184000000, 1108240107492643314063114240000, 25425833233403394290952098021376000000000, 67839608823081187608930897100800000000000, 1064102035269050218905833606927320350720000000

Offset

1,1

Links

Max Alekseyev, Table of n, a(n) for n = 1..18 (contains all terms below 10^100)

Jean-Marie De Koninck, Those Fascinating Numbers, Amer. Math. Soc., (2009), page 377.

Example

a(1) = 8314460009856000 = (7+8)*(7+3)*(7+1)*...*(7+6)*(7+0)*(7+0)*(7+0).

Crossrefs

Cf. A055482, A098113, A098114, A097371, A097372, A113756

Sequence in context: A011529 A136607 A257140 * A104836 A247156 A320865

Adjacent sequences: A115224 A115225 A115226 * A115228 A115229 A115230

Keyword

base,nonn

Author

Giovanni Resta, Jan 16 2006

Extensions

a(6)-a(18) from Max Alekseyev, Jan 25 2015

Status

approved