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A275171
Partition the j digits of n into blocks of k, with 1 <= k <= j-1, starting at left and multiply. Sum of these numbers equals n.
1
396, 1064, 1518, 1545, 4318, 4345, 4563, 12154, 21154, 145250, 517150, 532315, 43321250, 66710504, 175401008, 407902400, 492701500, 1148032202, 10144502500, 35308402400, 44916701500, 90751434020, 101445025000, 353084024000, 449167015000, 907514340200
OFFSET
1,1
COMMENTS
The number of partitions of k digits are [j-(j mod k)]/k. If j is not a multiple of k the last partition has j mod k digits. E.g.: the partitions of 3 digits of 5573670 are 557 and 367 plus a partition of one digit, 0 (here j=7 and k=3). - Paolo P. Lava, Aug 04 2016
EXAMPLE
3*9*6 + 39*6 = 396;
1*0*6*4 + 10*64 + 106*4 = 1064;
1*2*1*5*4 + 12*15*4 + 121*54 + 1215*4 = 12154.
MAPLE
P:=proc(q) local a, b, c, d, j, k, n;
for n from 1 to q do c:=0; for k from 1 to ilog10(n) do a:=1; b:=n; d:=ilog10(n)+1;
for j from 1 to trunc(d/k) do a:=a*(trunc(n/10^(d-j*k)) mod 10^k); od;
if d-trunc(d/k)*k>0 then a:=a*(n mod 10^(d-trunc(d/k)*k)); fi;
c:=c+a; od; if n=c then print(n); fi; od; end: P(10^6);
CROSSREFS
Cf. A275170.
Sequence in context: A230450 A247989 A126078 * A028299 A205628 A203934
KEYWORD
nonn,base,more
AUTHOR
Paolo P. Lava, Jul 19 2016
EXTENSIONS
a(18)-a(26) from Giovanni Resta, Jul 21 2016
STATUS
approved