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A067249 Digits of sigma(n) end in phi(n). 0
1, 6, 84, 112, 141, 294, 1188, 1320, 2508, 4584, 5406, 8850, 14270, 17416, 23320, 31152, 79035, 117576, 125576, 132066, 149877, 160664, 162514, 164024, 167970, 170980, 177744, 184584, 223286 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

EXAMPLE

sigma(79035) = 138240 ends in phi(79035) = 38240, so 79035 is a term of the sequence.

MATHEMATICA

(*returns true if a ends with b, false o.w.*) f[a_, b_] := Module[{c, d, e, g, h, i, r}, r = False; c = ToString[a]; d = ToString[b]; e = StringLength[c]; g = StringPosition[c, d]; h = Length[g]; If[h > 0, i = g[[h]]; If[i[[2]] == e, r = True]]; r]; Select[Range[10^5], f[DivisorSigma[1, # ], EulerPhi[ # ]] & ]

CROSSREFS

Sequence in context: A186661 A186659 A196256 * A155191 A054605 A119576

Adjacent sequences:  A067246 A067247 A067248 * A067250 A067251 A067252

KEYWORD

base,nonn

AUTHOR

Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Feb 20 2002

EXTENSIONS

More terms from Vladeta Jovovic (vladeta(AT)eunet.rs), Feb 22 2002

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.