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A281916 5th power analog of Keith numbers. 6
1, 28, 35, 36, 46, 51, 99, 109, 191, 239, 476, 491, 1022, 1126, 1358, 1362, 15156, 21581, 44270, 63377, 100164, 375830, 388148, 2749998, 5215505, 10158487, 81082532, 87643314, 410989134, 1485204944, 3496111364, 3829840893, 15889549579, 16107462404, 16766005098, 17608009898 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Like Keith numbers but starting from n^5 digits to reach n.

Consider the digits of n^5. Take their sum and repeat the process deleting the first addend and adding the previous sum. The sequence lists the numbers that after some number of iterations reach a sum equal to n.

LINKS

Table of n, a(n) for n=1..36.

EXAMPLE

109^5 = 15386239549:

1 + 5 + 3 + 8 + 6 + 2 + 3 + 9 + 5 + 4 + 9 = 55;

5 + 3 + 8 + 6 + 2 + 3 + 9 + 5 + 4 + 9 + 55 = 109.

MAPLE

with(numtheory): P:=proc(q, h, w) local a, b, k, t, v; global n; v:=array(1..h);

for n from 1 to q do b:=n^w; a:=[];

for k from 1 to ilog10(b)+1 do a:=[(b mod 10), op(a)]; b:=trunc(b/10); od;

for k from 1 to nops(a) do v[k]:=a[k]; od; b:=ilog10(n^w)+1;

t:=nops(a)+1; v[t]:=add(v[k], k=1..b); while v[t]<n do t:=t+1; v[t]:=add(v[k], k=t-b..t-1);

od; if v[t]=n then print(n); fi; od; end: P(10^6, 10000, 5);

CROSSREFS

Cf. A055576, A007629, A246544, A263534.

Cf. A274769, A274770, A281915, A281917, A281918, A281919, A281920, A281921.

Sequence in context: A330758 A214470 A055576 * A146077 A260637 A143186

Adjacent sequences:  A281913 A281914 A281915 * A281917 A281918 A281919

KEYWORD

nonn,base

AUTHOR

Paolo P. Lava, Feb 02 2017

EXTENSIONS

a(27)-a(28) from Jinyuan Wang, Jan 31 2020

a(29)-a(36) from Giovanni Resta, Jan 31 2020

STATUS

approved

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Last modified June 5 01:27 EDT 2020. Contains 334828 sequences. (Running on oeis4.)