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A293479 Composite numbers k = concat(MSD(k),x) such that the sum of the aliquot parts of k is equal to the sum of the aliquot parts of x. 0
1219, 1339, 3959, 4189, 7519, 11569, 11947, 27347, 35579, 37391, 38579, 45391, 46097, 77593, 81407, 94319, 94807, 95299, 96139, 97271, 99691, 102937, 106159, 107629, 115069, 131917, 137533, 158221, 168637, 201659, 223997, 339629, 345911, 352829, 362771, 363191 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

sigma(27347) - 27347 = 30240 - 27347 = 2893 and sigma(7347) - 7347 = 10240 - 7347 = 2893.

MAPLE

with(numtheory): P:=proc(q) local a, k, n, p, x, y; for n from 2 to q do

if not isprime(n) then x:=n mod 10^(ilog10(n));

if sigma(n)-n=sigma(x)-x then print(n); fi; fi; od; end: P(10^6);

CROSSREFS

Cf. A000030, A000203, A001065.

Sequence in context: A175964 A300408 A252600 * A031781 A069400 A233660

Adjacent sequences:  A293476 A293477 A293478 * A293480 A293481 A293482

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava, Oct 10 2017

STATUS

approved

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Last modified February 26 12:43 EST 2020. Contains 332280 sequences. (Running on oeis4.)