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A262252 Even Quasi-Carmichael numbers. 2
598, 1886, 11590, 21098, 24734, 32578, 91078, 95170, 107606, 134930, 143318, 179998, 253598, 258482, 259010, 287274, 361730, 374402, 568514, 706142, 751394, 831290, 920782, 1074026, 1105646, 1327562, 1514602, 1548318, 1579394, 1742830, 1794854, 1808678, 1952222 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Tim Johannes Ohrtmann, Table of n, a(n) for n = 1..84

EXAMPLE

598 is even, composite and squarefree and at least one nonzero integer b exists such that for every prime factor p of n, p+b divides n+b (2): 598 = 2*13*23 and 4, 15, 25 all divide 600.

PROG

(PARI) n=0; until(n==1000000, n+=2; if(!isprime(n), if(issquarefree(n), f=factor(n); k=0; b=0; until(b==n, b+=2; c=0; for(i=1, #f[, 1], if((n+b)%(f[i, 1]+b)>0, c++)); if(c==0, k++)); if(k>0, print1(n, ", ")))))

CROSSREFS

Cf. A029562, A029564, A029566, A029568, A029570, A257750.

Sequence in context: A251224 A210384 A215195 * A252265 A029562 A273810

Adjacent sequences:  A262249 A262250 A262251 * A262253 A262254 A262255

KEYWORD

nonn

AUTHOR

Tim Johannes Ohrtmann, Sep 16 2015

STATUS

approved

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Last modified February 27 11:20 EST 2021. Contains 341654 sequences. (Running on oeis4.)