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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.
4
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).
KEYWORD
base,nonn
AUTHOR
Giovanni Resta, Jan 16 2006
EXTENSIONS
a(6)-a(18) from Max Alekseyev, Jan 25 2015
STATUS
approved