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A316487
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Squares whose arithmetic mean of digits is 7 (i.e., the sum of digits is 7 times the number of digits).
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1
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2778889, 4695889, 5678689, 5697769, 5938969, 6568969, 6589489, 6848689, 6895876, 7974976, 7997584, 8779369, 9878449, 9966649, 299739969, 377796969, 396686889, 458687889, 467986689, 487658889, 488984769, 496977849, 538889796, 557998884, 559984896, 569967876
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OFFSET
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1,1
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COMMENTS
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Each term's number of digits is in A056991 (Numbers with digital root 1, 4, 7, or 9). For every term k in A056991, this sequence contains at least one k-digit term, with the exception of k=1 and k=4. (See A316480.)
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LINKS
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EXAMPLE
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17313^2 = 299739969, a 9-digit number whose digit sum is 2+9+9+7+3+9+9+6+9 = 63 = 7*9, so 299739969 is a term.
43474^2 = 1889988676, a 10-digit number whose digit sum is 1+8+8+9+9+8+8+6+7+6 = 70 = 7*10, so 1889988676 is a term.
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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