

A171493


"Kaprekar quadruples": digits of X^4 taken D at a time sum to X (where D is number of digits in X.)


2



1, 7, 45, 55, 67, 100, 433, 4950, 5050, 38212, 65068, 190576, 295075, 299035, 310024, 336700, 343333, 394615, 414558, 433566, 448228, 450550, 467236, 475497, 476191, 486486, 499500, 500500, 523513, 534898, 549550, 599743, 622414, 628408, 647362
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OFFSET

1,2


COMMENTS

Referred to as "natural" Kaprekar numbers on Munafo webpage because a(n) and the 4 pieces of a(n)^4 must all have the same number of digits (some of which can be leading zeros). Analogous to A053816 for squares, as opposed to A006886 and A045913 which allow irregular divisions.


LINKS

Robert Gerbicz, Table of n, a(n) for n = 1..10852
R. Munafo, Kaprekar Sequences


EXAMPLE

7^4 = 2401 ; 2+4+0+1 = 7. 67^4 = 20151121 ; 20+15+11+21 = 67. 4950^4 = 600372506250000 ; 0600+3725+0625+0000 = 4950.


CROSSREFS

Cf. A006886, A006887, A045913, A053816
Sequence in context: A221541 A327680 A156374 * A262772 A153492 A107125
Adjacent sequences: A171490 A171491 A171492 * A171494 A171495 A171496


KEYWORD

base,nonn


AUTHOR

Robert Munafo, Dec 10 2009


EXTENSIONS

Added term a(1)=1, Robert Gerbicz, Jul 28 2011


STATUS

approved



