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A048783 Numbers n such that prime(n) - sigma(n) - phi(n) = prime(n+1) - sigma(n+1) - phi(n+1), where sigma(n) = sum of divisors of n. 2
2, 33, 57, 62, 142, 201, 253, 302, 501, 542, 745, 877, 878, 913, 921, 1153, 1198, 1201, 1477, 1642, 1942, 1982, 2041, 2326, 2362, 2605, 2973, 3046, 3226, 3273, 3326, 3493, 3517, 3601, 3646, 3694, 3733, 3826, 3865, 3902, 4054, 4261, 4273, 4357, 4414, 4573 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..46.

PROG

(PARI) isok(n) = (prime(n) - sigma(n) - eulerphi(n) == prime(n+1) - sigma(n+1) - eulerphi(n+1)) \\ Michel Marcus, Jul 14 2013

CROSSREFS

Cf. A000040, A000203, A000010.

Sequence in context: A316736 A199551 A045932 * A116340 A003347 A303375

Adjacent sequences:  A048780 A048781 A048782 * A048784 A048785 A048786

KEYWORD

easy,nonn

AUTHOR

Naohiro Nomoto

STATUS

approved

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Last modified April 19 03:00 EDT 2019. Contains 322237 sequences. (Running on oeis4.)